input - Page 683 - Developer IT

Async ignored on AJAX requests on Nginx server

- by eComEvo

Despite sending an async request to the server over AJAX, the server will not respond until the previous unrelated request has finished. The following code is only broken in this way on Nginx, but runs perfectly on Apache. This call will start a background process and it waits for it to complete so it can display the final result. $.ajax({ type: 'GET', async: true, url: $(this).data('route'), data: $('input[name=data]').val(), dataType: 'json', success: function (data) { /* do stuff */} error: function (data) { /* handle errors */} }); The below is called after the above, which on Apache requires 100ms to execute and repeats itself, showing progress for data being written in the background: checkStatusInterval = setInterval(function () { $.ajax({ type: 'GET', async: false, cache: false, url: '/process-status?process=' + currentElement.attr('id'), dataType: 'json', success: function (data) { /* update progress bar and status message */ } }); }, 1000); Unfortunately, when this script is run from nginx, the above progress request never even finishes a single request until the first AJAX request that sent the data is done. If I change the async to TRUE in the above, it executes one every interval, but none of them complete until that very first AJAX request finishes. Here is the main nginx conf file: #user nobody; worker_processes 1; #error_log logs/error.log; #error_log logs/error.log notice; #error_log logs/error.log info; #pid logs/nginx.pid; events { worker_connections 1024; } http { include mime.types; default_type application/octet-stream; server_names_hash_bucket_size 64; # configure temporary paths # nginx is started with param -p, setting nginx path to serverpack installdir fastcgi_temp_path temp/fastcgi; uwsgi_temp_path temp/uwsgi; scgi_temp_path temp/scgi; client_body_temp_path temp/client-body 1 2; proxy_temp_path temp/proxy; log_format main '$remote_addr - $remote_user [$time_local] "$request" ' '$status $body_bytes_sent "$http_referer" ' '"$http_user_agent" "$http_x_forwarded_for"'; #access_log logs/access.log main; # Sendfile copies data between one FD and other from within the kernel. # More efficient than read() + write(), since the requires transferring data to and from the user space. sendfile on; # Tcp_nopush causes nginx to attempt to send its HTTP response head in one packet, # instead of using partial frames. This is useful for prepending headers before calling sendfile, # or for throughput optimization. tcp_nopush on; # don't buffer data-sends (disable Nagle algorithm). Good for sending frequent small bursts of data in real time. tcp_nodelay on; types_hash_max_size 2048; # Timeout for keep-alive connections. Server will close connections after this time. keepalive_timeout 90; # Number of requests a client can make over the keep-alive connection. This is set high for testing. keepalive_requests 100000; # allow the server to close the connection after a client stops responding. Frees up socket-associated memory. reset_timedout_connection on; # send the client a "request timed out" if the body is not loaded by this time. Default 60. client_header_timeout 20; client_body_timeout 60; # If the client stops reading data, free up the stale client connection after this much time. Default 60. send_timeout 60; # Size Limits client_body_buffer_size 64k; client_header_buffer_size 4k; client_max_body_size 8M; # FastCGI fastcgi_connect_timeout 60; fastcgi_send_timeout 120; fastcgi_read_timeout 300; # default: 60 secs; when step debugging with XDEBUG, you need to increase this value fastcgi_buffer_size 64k; fastcgi_buffers 4 64k; fastcgi_busy_buffers_size 128k; fastcgi_temp_file_write_size 128k; # Caches information about open FDs, freqently accessed files. open_file_cache max=200000 inactive=20s; open_file_cache_valid 30s; open_file_cache_min_uses 2; open_file_cache_errors on; # Turn on gzip output compression to save bandwidth. # http://wiki.nginx.org/HttpGzipModule gzip on; gzip_disable "MSIE [1-6]\.(?!.*SV1)"; gzip_http_version 1.1; gzip_vary on; gzip_proxied any; #gzip_proxied expired no-cache no-store private auth; gzip_comp_level 6; gzip_buffers 16 8k; gzip_types text/plain text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript application/javascript; # show all files and folders autoindex on; server { # access from localhost only listen 127.0.0.1:80; server_name localhost; root www; # the following default "catch-all" configuration, allows access to the server from outside. # please ensure your firewall allows access to tcp/port 80. check your "skype" config. # listen 80; # server_name _; log_not_found off; charset utf-8; access_log logs/access.log main; # handle files in the root path /www location / { index index.php index.html index.htm; } #error_page 404 /404.html; # redirect server error pages to the static page /50x.html # error_page 500 502 503 504 /50x.html; location = /50x.html { root www; } # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9100 # location ~ \.php$ { try_files $uri =404; fastcgi_pass 127.0.0.1:9100; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; include fastcgi_params; } # add expire headers location ~* ^.+.(gif|ico|jpg|jpeg|png|flv|swf|pdf|mp3|mp4|xml|txt|js|css)$ { expires 30d; } # deny access to .htaccess files (if Apache's document root concurs with nginx's one) # deny access to git & svn repositories location ~ /(\.ht|\.git|\.svn) { deny all; } } # include config files of "enabled" domains include domains-enabled/*.conf; } Here is the enabled domain conf file: access_log off; access_log C:/server/www/test.dev/logs/access.log; error_log C:/server/www/test.dev/logs/error.log; # HTTP Server server { listen 127.0.0.1:80; server_name test.dev; root C:/server/www/test.dev/public; index index.php; rewrite_log on; default_type application/octet-stream; #include /etc/nginx/mime.types; # Include common configurations. include domains-common/location.conf; } # HTTPS server server { listen 443 ssl; server_name test.dev; root C:/server/www/test.dev/public; index index.php; rewrite_log on; default_type application/octet-stream; #include /etc/nginx/mime.types; # Include common configurations. include domains-common/location.conf; include domains-common/ssl.conf; } Contents of ssl.conf: # OpenSSL for HTTPS connections. ssl on; ssl_certificate C:/server/bin/openssl/certs/cert.pem; ssl_certificate_key C:/server/bin/openssl/certs/cert.key; ssl_session_timeout 5m; ssl_protocols SSLv3 TLSv1 TLSv1.1 TLSv1.2; ssl_ciphers HIGH:!aNULL:!MD5; ssl_prefer_server_ciphers on; # Pass the PHP scripts to FastCGI server listening on 127.0.0.1:9100 location ~ \.php$ { try_files $uri =404; fastcgi_param HTTPS on; fastcgi_pass 127.0.0.1:9100; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; include fastcgi_params; } Contents of location.conf: # Remove trailing slash to please Laravel routing system. if (!-d $request_filename) { rewrite ^/(.+)/$ /$1 permanent; } location / { try_files $uri $uri/ /index.php?$query_string; } # We don't need .ht files with nginx. location ~ /(\.ht|\.git|\.svn) { deny all; } # Added cache headers for images. location ~* \.(png|jpg|jpeg|gif)$ { expires 30d; log_not_found off; } # Only 3 hours on CSS/JS to allow me to roll out fixes during early weeks. location ~* \.(js|css)$ { expires 3h; log_not_found off; } # Add expire headers. location ~* ^.+.(gif|ico|jpg|jpeg|png|flv|swf|pdf|mp3|mp4|xml|txt)$ { expires 30d; } # Pass the PHP scripts to FastCGI server listening on 127.0.0.1:9100 location ~ \.php$ { try_files $uri /index.php =404; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; include fastcgi_params; fastcgi_pass 127.0.0.1:9100; } Any ideas where this is going wrong?

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OpenVPN Client timing out

- by Austin

I recently installed OpenVPN on my Ubuntu VPS. Whenenver I try to connect to it, I can establish a connection just fine. However, everything I try to connect to times out. If I try to ping something, it will resolve the IP, but will time out after resolving the IP. (So DNS Server seems to be working correctly) My server.conf has this relevant information (At least I think it's relevant. I'm not sure if you need more or not) # Which local IP address should OpenVPN # listen on? (optional) ;local a.b.c.d # Which TCP/UDP port should OpenVPN listen on? # If you want to run multiple OpenVPN instances # on the same machine, use a different port # number for each one. You will need to # open up this port on your firewall. port 1194 # TCP or UDP server? ;proto tcp proto udp # "dev tun" will create a routed IP tunnel, # "dev tap" will create an ethernet tunnel. # Use "dev tap0" if you are ethernet bridging # and have precreated a tap0 virtual interface # and bridged it with your ethernet interface. # If you want to control access policies # over the VPN, you must create firewall # rules for the the TUN/TAP interface. # On non-Windows systems, you can give # an explicit unit number, such as tun0. # On Windows, use "dev-node" for this. # On most systems, the VPN will not function # unless you partially or fully disable # the firewall for the TUN/TAP interface. ;dev tap dev tun # Windows needs the TAP-Win32 adapter name # from the Network Connections panel if you # have more than one. On XP SP2 or higher, # you may need to selectively disable the # Windows firewall for the TAP adapter. # Non-Windows systems usually don't need this. ;dev-node MyTap # SSL/TLS root certificate (ca), certificate # (cert), and private key (key). Each client # and the server must have their own cert and # key file. The server and all clients will # use the same ca file. # # See the "easy-rsa" directory for a series # of scripts for generating RSA certificates # and private keys. Remember to use # a unique Common Name for the server # and each of the client certificates. # # Any X509 key management system can be used. # OpenVPN can also use a PKCS #12 formatted key file # (see "pkcs12" directive in man page). ca ca.crt cert server.crt key server.key # This file should be kept secret # Diffie hellman parameters. # Generate your own with: # openssl dhparam -out dh1024.pem 1024 # Substitute 2048 for 1024 if you are using # 2048 bit keys. dh dh1024.pem # Configure server mode and supply a VPN subnet # for OpenVPN to draw client addresses from. # The server will take 10.8.0.1 for itself, # the rest will be made available to clients. # Each client will be able to reach the server # on 10.8.0.1. Comment this line out if you are # ethernet bridging. See the man page for more info. server 10.8.0.0 255.255.255.0 # Maintain a record of client <-> virtual IP address # associations in this file. If OpenVPN goes down or # is restarted, reconnecting clients can be assigned # the same virtual IP address from the pool that was # previously assigned. ifconfig-pool-persist ipp.txt # Configure server mode for ethernet bridging. # You must first use your OS's bridging capability # to bridge the TAP interface with the ethernet # NIC interface. Then you must manually set the # IP/netmask on the bridge interface, here we # assume 10.8.0.4/255.255.255.0. Finally we # must set aside an IP range in this subnet # (start=10.8.0.50 end=10.8.0.100) to allocate # to connecting clients. Leave this line commented # out unless you are ethernet bridging. ;server-bridge 10.8.0.4 255.255.255.0 10.8.0.50 10.8.0.100 # Configure server mode for ethernet bridging # using a DHCP-proxy, where clients talk # to the OpenVPN server-side DHCP server # to receive their IP address allocation # and DNS server addresses. You must first use # your OS's bridging capability to bridge the TAP # interface with the ethernet NIC interface. # Note: this mode only works on clients (such as # Windows), where the client-side TAP adapter is # bound to a DHCP client. ;server-bridge # Push routes to the client to allow it # to reach other private subnets behind # the server. Remember that these # private subnets will also need # to know to route the OpenVPN client # address pool (10.8.0.0/255.255.255.0) # back to the OpenVPN server. ;push "route 192.168.10.0 255.255.255.0" ;push "route 192.168.20.0 255.255.255.0" # To assign specific IP addresses to specific # clients or if a connecting client has a private # subnet behind it that should also have VPN access, # use the subdirectory "ccd" for client-specific # configuration files (see man page for more info). # EXAMPLE: Suppose the client # having the certificate common name "Thelonious" # also has a small subnet behind his connecting # machine, such as 192.168.40.128/255.255.255.248. # First, uncomment out these lines: ;client-config-dir ccd ;route 192.168.40.128 255.255.255.248 # Then create a file ccd/Thelonious with this line: # iroute 192.168.40.128 255.255.255.248 # This will allow Thelonious' private subnet to # access the VPN. This example will only work # if you are routing, not bridging, i.e. you are # using "dev tun" and "server" directives. # EXAMPLE: Suppose you want to give # Thelonious a fixed VPN IP address of 10.9.0.1. # First uncomment out these lines: ;client-config-dir ccd ;route 10.9.0.0 255.255.255.252 # Then add this line to ccd/Thelonious: # ifconfig-push 10.9.0.1 10.9.0.2 # Suppose that you want to enable different # firewall access policies for different groups # of clients. There are two methods: # (1) Run multiple OpenVPN daemons, one for each # group, and firewall the TUN/TAP interface # for each group/daemon appropriately. # (2) (Advanced) Create a script to dynamically # modify the firewall in response to access # from different clients. See man # page for more info on learn-address script. ;learn-address ./script # If enabled, this directive will configure # all clients to redirect their default # network gateway through the VPN, causing # all IP traffic such as web browsing and # and DNS lookups to go through the VPN # (The OpenVPN server machine may need to NAT # or bridge the TUN/TAP interface to the internet # in order for this to work properly). push "redirect-gateway def1 bypass-dhcp" push "dhcp-option DNS 8.8.8.8" # Certain Windows-specific network settings # can be pushed to clients, such as DNS # or WINS server addresses. CAVEAT: # http://openvpn.net/faq.html#dhcpcaveats # The addresses below refer to the public # DNS servers provided by opendns.com. ;push "dhcp-option DNS 8.8.8.8" push "dhcp-option DNS 8.8.4.4" # Uncomment this directive to allow different # clients to be able to "see" each other. # By default, clients will only see the server. # To force clients to only see the server, you # will also need to appropriately firewall the # server's TUN/TAP interface. ;client-to-client # Uncomment this directive if multiple clients # might connect with the same certificate/key # files or common names. This is recommended # only for testing purposes. For production use, # each client should have its own certificate/key # pair. # # IF YOU HAVE NOT GENERATED INDIVIDUAL # CERTIFICATE/KEY PAIRS FOR EACH CLIENT, # EACH HAVING ITS OWN UNIQUE "COMMON NAME", # UNCOMMENT THIS LINE OUT. ;duplicate-cn # The keepalive directive causes ping-like # messages to be sent back and forth over # the link so that each side knows when # the other side has gone down. # Ping every 10 seconds, assume that remote # peer is down if no ping received during # a 120 second time period. keepalive 10 120 # For extra security beyond that provided # by SSL/TLS, create an "HMAC firewall" # to help block DoS attacks and UDP port flooding. # # Generate with: # openvpn --genkey --secret ta.key # # The server and each client must have # a copy of this key. # The second parameter should be '0' # on the server and '1' on the clients. ;tls-auth ta.key 0 # This file is secret # Select a cryptographic cipher. # This config item must be copied to # the client config file as well. ;cipher BF-CBC # Blowfish (default) ;cipher AES-128-CBC # AES ;cipher DES-EDE3-CBC # Triple-DES # Enable compression on the VPN link. # If you enable it here, you must also # enable it in the client config file. comp-lzo # The maximum number of concurrently connected # clients we want to allow. ;max-clients 100 # It's a good idea to reduce the OpenVPN # daemon's privileges after initialization. # # You can uncomment this out on # non-Windows systems. ;user nobody ;group nogroup # The persist options will try to avoid # accessing certain resources on restart # that may no longer be accessible because # of the privilege downgrade. persist-key persist-tun # Output a short status file showing # current connections, truncated # and rewritten every minute. status openvpn-status.log # By default, log messages will go to the syslog (or # on Windows, if running as a service, they will go to # the "\Program Files\OpenVPN\log" directory). # Use log or log-append to override this default. # "log" will truncate the log file on OpenVPN startup, # while "log-append" will append to it. Use one # or the other (but not both). ;log openvpn.log ;log-append openvpn.log # Set the appropriate level of log # file verbosity. # # 0 is silent, except for fatal errors # 4 is reasonable for general usage # 5 and 6 can help to debug connection problems # 9 is extremely verbose verb 3 # Silence repeating messages. At most 20 # sequential messages of the same message # category will be output to the log. ;mute 20 I've tried on multiple computers by the way. The same result on all of them. What could be wrong? Thanks in advance, and if you need other information I'll gladly post it. Information for new comments root@vps:~# iptables -L -n -v Chain INPUT (policy ACCEPT 862K packets, 51M bytes) pkts bytes target prot opt in out source destination Chain FORWARD (policy ACCEPT 3 packets, 382 bytes) pkts bytes target prot opt in out source destination 0 0 ACCEPT all -- * * 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED 4641 298K ACCEPT all -- * * 10.8.0.0/24 0.0.0.0/0 0 0 REJECT all -- * * 0.0.0.0/0 0.0.0.0/0 reject-with icmp-port-unreachable Chain OUTPUT (policy ACCEPT 1671K packets, 2378M bytes) pkts bytes target prot opt in out source destination And root@vps:~# iptables -t nat -L -n -v Chain PREROUTING (policy ACCEPT 17937 packets, 2013K bytes) pkts bytes target prot opt in out source destination Chain POSTROUTING (policy ACCEPT 8975 packets, 562K bytes) pkts bytes target prot opt in out source destination 1579 103K SNAT all -- * * 10.8.0.0/24 0.0.0.0/0 to:SERVERIP Chain OUTPUT (policy ACCEPT 8972 packets, 562K bytes) pkts bytes target prot opt in out source destination

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Use DivX settings to encode to mp4 with ffmpeg

- by sjngm

I'm used to use VirtualDub to encode a video to AVI container with DivX-codec (and MP3 for audio). Now I'm planning to use ffmpeg to encode videos to MP4 container with h264-codec. What I've figured out is that I need to use libx264 and one of those presets to make anything work. However, I'm amazed about the video bitrate ffmpeg uses for encoding. What I currently have is this little batch file: @ECHO OFF SETLOCAL SET IN=source.avs SET FFMPEG_PATH=C:\Program Files (x86)\ffmpeg SET PRESET=-fpre "%FFMPEG_PATH%\presets\libx264-lossless_slow.ffpreset" SET AUDIO=-acodec libmp3lame -ab 128000 SET VIDEO=-vcodec libx264 -vb 1978000 "%FFMPEG_PATH%\ffmpeg.exe" -i %IN% %AUDIO% %VIDEO% %PRESET% test.mp4 ENDLOCAL With this I tell ffmpeg to use 1978k as the bitrate, but ffmpeg uses 15000k+! I tried other presets, but they don't use my specified bitrate. Here are the presets I have: libx264-baseline.ffpreset libx264-ipod320.ffpreset libx264-ipod640.ffpreset libx264-lossless_fast.ffpreset libx264-lossless_max.ffpreset libx264-lossless_medium.ffpreset libx264-lossless_slow.ffpreset libx264-lossless_slower.ffpreset libx264-lossless_ultrafast.ffpreset ffmpeg version: FFmpeg git-N-29181-ga304071 libavutil 50. 40. 1 / 50. 40. 1 libavcodec 52.120. 0 / 52.120. 0 libavformat 52.108. 0 / 52.108. 0 libavdevice 52. 4. 0 / 52. 4. 0 libavfilter 1. 79. 0 / 1. 79. 0 libswscale 0. 13. 0 / 0. 13. 0 Note that I don't use the latest version as it has problems with spaces in filenames. Here's what seems to be the full parameter list DivX 6.9.2 uses: -bvnn 1978000 -vbv 218691200,100663296,100663296 -dir "C:\Users\sjngm\AppData\Roaming\DivX\DivX Codec" -w -b 1 -use_presets=1 -preset=10 -windowed_fullsearch=2 -thread_delay=1 What command line parameters would that be for ffmpeg? EDIT: Going with slhck's suggestion I tried a new 32-bit version. I have no idea if that is 0.9 or newer, I can't find that info. ffmpeg version N-36890-g67f5650 libavutil 51. 34.100 / 51. 34.100 libavcodec 53. 56.105 / 53. 56.105 libavformat 53. 30.100 / 53. 30.100 libavdevice 53. 4.100 / 53. 4.100 libavfilter 2. 59.100 / 2. 59.100 libswscale 2. 1.100 / 2. 1.100 libswresample 0. 6.100 / 0. 6.100 libpostproc 51. 2.100 / 51. 2.100 I reworked my batch file to look like this (interestingly enough I can't find parameter -vprofile in the documentation): @ECHO OFF SETLOCAL SET IN=VTS_01_1.avs SET FFMPEG_PATH=C:\Program Files (x86)\ffmpeg SET PRESET=-vprofile high -preset veryslow SET AUDIO=-acodec libmp3lame -ab 128000 SET VIDEO=-vcodec libx264 -vb 1978000 "%FFMPEG_PATH%\ffmpeg.exe" -i %IN% %AUDIO% %PRESET% %VIDEO% test.mp4 ENDLOCAL I see that it now uses the bitrate properly (thanks to LongNeckbeard for pointing out that the lossless-stuff ignores the bitrate!). Just in case you wonder how I came up with the 1978000, I'm using this formula which I found valid for DivX-files (I'm guessing the bitrate won't change that much for h264): width * height * 25 * 0.22 / 1000 I'm not sure if the 0.22 correlates with the CRF somehow. Overall I forgot to say the I will use a two-pass scenario, which is why I don't use the CRF here. I will try to read more about this. Currently I'm just trying to get something running that shows me that I'm doing something right (ffmpeg isn't the easiest tool to understand ;)). C:\Program Files (x86)\ffmpeg\ffmpeg.exe" -i VTS_01_1.avs -acodec libmp3lame -ab 128000 -vcodec libx264 -vb 1978000 -vprofile high -preset veryslow test.mp4 The output is now: ffmpeg version N-36890-g67f5650 Copyright (c) 2000-2012 the FFmpeg developers built on Jan 16 2012 21:57:13 with gcc 4.6.2 configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-runtime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid --enable-zlib libavutil 51. 34.100 / 51. 34.100 libavcodec 53. 56.105 / 53. 56.105 libavformat 53. 30.100 / 53. 30.100 libavdevice 53. 4.100 / 53. 4.100 libavfilter 2. 59.100 / 2. 59.100 libswscale 2. 1.100 / 2. 1.100 libswresample 0. 6.100 / 0. 6.100 libpostproc 51. 2.100 / 51. 2.100 Input #0, avs, from 'VTS_01_1.avs': Duration: 00:58:46.12, start: 0.000000, bitrate: 0 kb/s Stream #0:0: Video: rawvideo (YV12 / 0x32315659), yuv420p, 576x448, 77414 kb/s, 25 tbr, 25 tbn, 25 tbc Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz, 2 channels, s16, 1536 kb/s File 'test.mp4' already exists. Overwrite ? [y/N] y w:576 h:448 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param: [libx264 @ 05A2C400] using cpu capabilities: MMX2 SSE2Fast FastShuffle SSEMisalign LZCNT [libx264 @ 05A2C400] profile High, level 3.1 [libx264 @ 05A2C400] 264 - core 120 r2120 0c7dab9 - H.264/MPEG-4 AVC codec - Copyleft 2003-2011 - http://www.videolan.org/x264.html - options: cabac=1 ref=16 deblock=1:0:0 analyse=0x3:0x133 me=umh subme=10 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=24 chroma_me=1 trellis=2 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=3 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=8 b_pyramid=2 b_adapt=2 b_bias=0 direct=3 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=60 rc=abr mbtree=1 bitrate=1978 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00 Output #0, mp4, to 'test.mp4': Metadata: encoder : Lavf53.30.100 Stream #0:0: Video: h264 (![0][0][0] / 0x0021), yuv420p, 576x448, q=-1--1, 1978 kb/s, 25 tbn, 25 tbc Stream #0:1: Audio: mp3 (i[0][0][0] / 0x0069), 48000 Hz, 2 channels, s16, 128 kb/s Stream mapping: Stream #0:0 -> #0:0 (rawvideo -> libx264) Stream #0:1 -> #0:1 (pcm_s16le -> libmp3lame) Press [q] to stop, [?] for help frame= 0 fps= 0 q=0.0 size= 0kB time=00:00:00.00 bitrate= 0.0kbits/s frame= 0 fps= 0 q=0.0 size= 0kB time=00:00:00.00 bitrate= 0.0kbits/s frame= 0 fps= 0 q=0.0 size= 0kB time=00:00:00.00 bitrate= 0.0kbits/s frame= 3 fps= 1 q=22.0 size= 39kB time=00:00:00.04 bitrate=8063.8kbits/ frame= 8 fps= 2 q=22.0 size= 82kB time=00:00:00.24 bitrate=2801.3kbits/ frame= 13 fps= 3 q=23.0 size= 120kB time=00:00:00.44 bitrate=2229.5kbits/ frame= 16 fps= 4 q=23.0 size= 147kB time=00:00:00.56 bitrate=2156.7kbits/ frame= 20 fps= 4 q=22.0 size= 175kB time=00:00:00.72 bitrate=1987.4kbits/ : video:4387kB audio:273kB global headers:0kB muxing overhead 0.260038% [libx264 @ 05A2C400] frame I:2 Avg QP:19.53 size: 29850 [libx264 @ 05A2C400] frame P:76 Avg QP:22.24 size: 19541 [libx264 @ 05A2C400] frame B:359 Avg QP:25.93 size: 8210 [libx264 @ 05A2C400] consecutive B-frames: 0.5% 0.5% 0.0% 8.2% 17.2% 52.2% 16.0% 5.5% 0.0% [libx264 @ 05A2C400] mb I I16..4: 5.4% 75.3% 19.3% [libx264 @ 05A2C400] mb P I16..4: 1.3% 16.5% 2.2% P16..4: 36.3% 28.6% 12.7% 1.8% 0.2% skip: 0.4% [libx264 @ 05A2C400] mb B I16..4: 0.4% 3.8% 0.3% B16..8: 40.0% 18.4% 4.7% direct:18.5% skip:13.9% L0:45.4% L1:38.1% BI:16.5% [libx264 @ 05A2C400] final ratefactor: 20.35 [libx264 @ 05A2C400] 8x8 transform intra:83.1% inter:68.5% [libx264 @ 05A2C400] direct mvs spatial:99.2% temporal:0.8% [libx264 @ 05A2C400] coded y,uvDC,uvAC intra: 64.9% 83.4% 49.2% inter: 49.0% 50.4% 4.4% [libx264 @ 05A2C400] i16 v,h,dc,p: 25% 22% 27% 26% [libx264 @ 05A2C400] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 10% 7% 23% 9% 10% 10% 10%10% 13% [libx264 @ 05A2C400] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 12% 11% 13% 9% 12% 11% 10% 9% 12% [libx264 @ 05A2C400] i8c dc,h,v,p: 42% 28% 16% 14% [libx264 @ 05A2C400] Weighted P-Frames: Y:18.4% UV:7.9% [libx264 @ 05A2C400] ref P L0: 29.1% 11.3% 15.7% 7.3% 6.9% 4.9% 5.1% 3.4%3.9% 2.7% 2.8% 1.8% 1.7% 1.2% 1.4% 0.9% [libx264 @ 05A2C400] ref B L0: 68.8% 11.4% 5.5% 2.9% 2.3% 1.9% 1.5% 1.1%1.1% 1.0% 0.9% 0.7% 0.5% 0.3% 0.1% [libx264 @ 05A2C400] ref B L1: 91.9% 8.1% [libx264 @ 05A2C400] kb/s:2055.88 As far as I'm concerned it doesn't look that bad to me.

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Why do ICMP Redirct Host happen?

- by El Barto

I'm setting up a Debian box as a router for 4 subnets. For that I have defined 4 virtual interfaces on the NIC where the LAN is connected (eth1). eth1 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.1.1 Bcast:10.1.1.255 Mask:255.255.255.0 inet6 addr: fe80::960c:6dff:fe82:d98/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:6026521 errors:0 dropped:0 overruns:0 frame:0 TX packets:35331299 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:673201397 (642.0 MiB) TX bytes:177276932 (169.0 MiB) Interrupt:19 Base address:0x6000 eth1:0 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.2.1 Bcast:10.1.2.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:19 Base address:0x6000 eth1:1 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.3.1 Bcast:10.1.3.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:19 Base address:0x6000 eth1:2 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.4.1 Bcast:10.1.4.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:19 Base address:0x6000 eth2 Link encap:Ethernet HWaddr 6c:f0:49:a4:47:38 inet addr:192.168.1.10 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::6ef0:49ff:fea4:4738/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:199809345 errors:0 dropped:0 overruns:0 frame:0 TX packets:158362936 errors:0 dropped:0 overruns:0 carrier:1 collisions:0 txqueuelen:1000 RX bytes:3656983762 (3.4 GiB) TX bytes:1715848473 (1.5 GiB) Interrupt:27 eth3 Link encap:Ethernet HWaddr 94:0c:6d:82:c8:72 inet addr:192.168.2.5 Bcast:192.168.2.255 Mask:255.255.255.0 inet6 addr: fe80::960c:6dff:fe82:c872/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:110814 errors:0 dropped:0 overruns:0 frame:0 TX packets:73386 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:16044901 (15.3 MiB) TX bytes:42125647 (40.1 MiB) Interrupt:20 Base address:0x2000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:22351 errors:0 dropped:0 overruns:0 frame:0 TX packets:22351 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:2625143 (2.5 MiB) TX bytes:2625143 (2.5 MiB) tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 inet addr:10.8.0.1 P-t-P:10.8.0.2 Mask:255.255.255.255 UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1 RX packets:41358924 errors:0 dropped:0 overruns:0 frame:0 TX packets:23116350 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 RX bytes:3065505744 (2.8 GiB) TX bytes:1324358330 (1.2 GiB) I have two other computers connected to this network. One has IP 10.1.1.12 (subnet mask 255.255.255.0) and the other one 10.1.2.20 (subnet mask 255.255.255.0). I want to be able to reach 10.1.1.12 from 10.1.2.20. Since packet forwarding is enabled in the router and the policy of the FORWARD chain is ACCEPT (and there are no other rules), I understand that there should be no problem to ping from 10.1.2.20 to 10.1.1.12 going through the router. However, this is what I get: $ ping -c15 10.1.1.12 PING 10.1.1.12 (10.1.1.12): 56 data bytes Request timeout for icmp_seq 0 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 81d4 0 0000 3f 01 e2b3 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 1 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 899b 0 0000 3f 01 daec 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 2 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 78fe 0 0000 3f 01 eb89 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 3 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 14b8 0 0000 3f 01 4fd0 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 4 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 8ef7 0 0000 3f 01 d590 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 5 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 ec9d 0 0000 3f 01 77ea 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 6 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 70e6 0 0000 3f 01 f3a1 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 7 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 b0d2 0 0000 3f 01 b3b5 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 8 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 f8b4 0 0000 3f 01 6bd3 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 9 Request timeout for icmp_seq 10 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 1c95 0 0000 3f 01 47f3 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 11 Request timeout for icmp_seq 12 Request timeout for icmp_seq 13 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 62bc 0 0000 3f 01 01cc 10.1.2.20 10.1.1.12 Why does this happen? From what I've read the Redirect Host response has something to do with the fact that the two hosts are in the same network and there being a shorter route (or so I understood). They are in fact in the same physical network, but why would there be a better route if they are not on the same subnet (they can't see each other)? What am I missing? Some extra info you might want to see: # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.8.0.2 0.0.0.0 255.255.255.255 UH 0 0 0 tun0 127.0.0.1 0.0.0.0 255.255.255.255 UH 0 0 0 lo 192.168.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth3 10.8.0.0 10.8.0.2 255.255.255.0 UG 0 0 0 tun0 192.168.1.0 0.0.0.0 255.255.255.0 U 1 0 0 eth2 10.1.4.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.1.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.1.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.1.3.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth2 0.0.0.0 192.168.2.1 0.0.0.0 UG 100 0 0 eth3 # iptables -L -n Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination # iptables -L -n -t nat Chain PREROUTING (policy ACCEPT) target prot opt source destination Chain POSTROUTING (policy ACCEPT) target prot opt source destination MASQUERADE all -- !10.0.0.0/8 10.0.0.0/8 MASQUERADE all -- 10.0.0.0/8 !10.0.0.0/8 Chain OUTPUT (policy ACCEPT) target prot opt source destination

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Scripts help FIND command via atime output to multiple files

- by sswagner

here is a script I have wrote that I need help with. in the script I do a find for any file that has not been access for over 30 days, 60, 90, 180, 270 & 365 days. This works just fine. however, this takes a few days just to finish the 30 day portion. it is scanning a NAS. (millions and millions of files) as you see, the 30 day information really holds all the data need for the rest of the scripts. the 60, 90, etc. portion of the script are just redoing the same effort as the 30 day portion, except for an extended time frame. it would save in this case weeks worth of re-scanning if some how the 60, 90 180, etc.. portions could just get its data from the 30 day output. this is where I am asking for help. the output is just like an ls -l command. and you can also see from the output below, there are multiple years in this output. the script is attached and printed below. total 24 -rw-r--r-- 1 root bin 60 Apr 12 13:07 config_file -rw-r--r-- 1 root bin 9 Apr 12 13:07 config_file.InProgress -rw-r--r-- 1 root bin 0 Apr 12 13:07 config_file.sids -rw-r--r-- 1 root bin 1284 Apr 19 10:41 rpt_file -rw-r--r-- 1 16074 5003 20083 Apr 26 2002 /nas/quota/slot_2/CR_APP002/eb_ora_bin1/sun8/product/9.2s/oem_webstage/oracle/sysman/qtour/console/dat1_01.gif -rw-r--r-- 1 16074 5003 20088 Apr 26 2002 /nas/quota/slot_2/CR_APP002/eb_ora_bin1/sun8/product/9.2s/oem_webstage/oracle/sysman/qtour/console/set1_04.gif -rw-r--r-- 1 16074 5003 2008 Apr 26 2002 /nas/quota/slot_2/CR_APP002/eb_ora_bin1/sun8/product/9.2s/oem_webstage/oracle/sysman/qtour/oapps/get2_03.htm -rw-r--r-- 1 16074 5003 20083 Apr 26 2002 /nas/quota/slot_2/CR_APP002/eb_ora_bin1/sun8/product/9.2s/oem_webstage/oracle/sysman/qtour/oapps/per1_01.gif any help is appreciated. these are linux distro boxes, so I am sure perl is on there too if needed.. Thanks! !/bin/ksh # search shares for files that have not been accessed for a certain time. NOTE: $IN = input search $OUT = output directory for text file # TESTS Numeric arguments can be specified as # +n for greater than n, -n for less than n, n for exactly n. # -atime n File was last accessed n*24 hours ago. # # IN1=/nas/quota/slot_2/CR* IN2=/nas/quota/slot_3/CR* IN3=/nas/quota/slot_4/CR* IN4=/nas/quota/slot_5/CR* OUT=/nas/quota/slot_3/CR_PRJ144/steve mkdir ${OUT} for dir in ${IN1}; do find $dir -atime +30 -exec ls -l '{}' \; ${OUT}/30days.txt; done for dir in ${IN2}; do find $dir -atime +30 -exec ls -l '{}' \; ${OUT}/30days.txt; done for dir in ${IN3}; do find $dir -atime +30 -exec ls -l '{}' \; ${OUT}/30days.txt; done for dir in ${IN4}; do find $dir -atime +30 -exec ls -l '{}' \; ${OUT}/30days.txt; done for dir in ${IN1}; do find $dir -atime +60 -exec ls -l '{}' \; ${OUT}/60days.txt; done for dir in ${IN2}; do find $dir -atime +60 -exec ls -l '{}' \; ${OUT}/60days.txt; done for dir in ${IN3}; do find $dir -atime +60 -exec ls -l '{}' \; ${OUT}/60days.txt; done for dir in ${IN4}; do find $dir -atime +60 -exec ls -l '{}' \; ${OUT}/60days.txt; done for dir in ${IN1}; do find $dir -atime +90 -exec ls -l '{}' \; ${OUT}/90days.txt; done for dir in ${IN2}; do find $dir -atime +90 -exec ls -l '{}' \; ${OUT}/90days.txt; done for dir in ${IN3}; do find $dir -atime +90 -exec ls -l '{}' \; ${OUT}/90days.txt; done for dir in ${IN4}; do find $dir -atime +90 -exec ls -l '{}' \; ${OUT}/90days.txt; done for dir in ${IN1}; do find $dir -atime +180 -exec ls -l '{}' \; ${OUT}/180days.txt; done for dir in ${IN2}; do find $dir -atime +180 -exec ls -l '{}' \; ${OUT}/180days.txt; done for dir in ${IN3}; do find $dir -atime +180 -exec ls -l '{}' \; ${OUT}/180days.txt; done for dir in ${IN4}; do find $dir -atime +180 -exec ls -l '{}' \; ${OUT}/180days.txt; done for dir in ${IN1}; do find $dir -atime +270 -exec ls -l '{}' \; ${OUT}/270days.txt; done for dir in ${IN2}; do find $dir -atime +270 -exec ls -l '{}' \; ${OUT}/270days.txt; done for dir in ${IN3}; do find $dir -atime +270 -exec ls -l '{}' \; ${OUT}/270days.txt; done for dir in ${IN4}; do find $dir -atime +270 -exec ls -l '{}' \; ${OUT}/270days.txt; done for dir in ${IN1}; do find $dir -atime +365 -exec ls -l '{}' \; ${OUT}/365days.txt; done for dir in ${IN2}; do find $dir -atime +365 -exec ls -l '{}' \; ${OUT}/365days.txt; done for dir in ${IN3}; do find $dir -atime +365 -exec ls -l '{}' \; ${OUT}/365days.txt; done for dir in ${IN4}; do find $dir -atime +365 -exec ls -l '{}' \; ${OUT}/365days.txt; done

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Why do ICMP Redirect Host happen?

- by El Barto

I'm setting up a Debian box as a router for 4 subnets. For that I have defined 4 virtual interfaces on the NIC where the LAN is connected (eth1). eth1 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.1.1 Bcast:10.1.1.255 Mask:255.255.255.0 inet6 addr: fe80::960c:6dff:fe82:d98/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:6026521 errors:0 dropped:0 overruns:0 frame:0 TX packets:35331299 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:673201397 (642.0 MiB) TX bytes:177276932 (169.0 MiB) Interrupt:19 Base address:0x6000 eth1:0 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.2.1 Bcast:10.1.2.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:19 Base address:0x6000 eth1:1 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.3.1 Bcast:10.1.3.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:19 Base address:0x6000 eth1:2 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.4.1 Bcast:10.1.4.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:19 Base address:0x6000 eth2 Link encap:Ethernet HWaddr 6c:f0:49:a4:47:38 inet addr:192.168.1.10 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::6ef0:49ff:fea4:4738/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:199809345 errors:0 dropped:0 overruns:0 frame:0 TX packets:158362936 errors:0 dropped:0 overruns:0 carrier:1 collisions:0 txqueuelen:1000 RX bytes:3656983762 (3.4 GiB) TX bytes:1715848473 (1.5 GiB) Interrupt:27 eth3 Link encap:Ethernet HWaddr 94:0c:6d:82:c8:72 inet addr:192.168.2.5 Bcast:192.168.2.255 Mask:255.255.255.0 inet6 addr: fe80::960c:6dff:fe82:c872/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:110814 errors:0 dropped:0 overruns:0 frame:0 TX packets:73386 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:16044901 (15.3 MiB) TX bytes:42125647 (40.1 MiB) Interrupt:20 Base address:0x2000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:22351 errors:0 dropped:0 overruns:0 frame:0 TX packets:22351 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:2625143 (2.5 MiB) TX bytes:2625143 (2.5 MiB) tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 inet addr:10.8.0.1 P-t-P:10.8.0.2 Mask:255.255.255.255 UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1 RX packets:41358924 errors:0 dropped:0 overruns:0 frame:0 TX packets:23116350 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 RX bytes:3065505744 (2.8 GiB) TX bytes:1324358330 (1.2 GiB) I have two other computers connected to this network. One has IP 10.1.1.12 (subnet mask 255.255.255.0) and the other one 10.1.2.20 (subnet mask 255.255.255.0). I want to be able to reach 10.1.1.12 from 10.1.2.20. Since packet forwarding is enabled in the router and the policy of the FORWARD chain is ACCEPT (and there are no other rules), I understand that there should be no problem to ping from 10.1.2.20 to 10.1.1.12 going through the router. However, this is what I get: $ ping -c15 10.1.1.12 PING 10.1.1.12 (10.1.1.12): 56 data bytes Request timeout for icmp_seq 0 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 81d4 0 0000 3f 01 e2b3 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 1 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 899b 0 0000 3f 01 daec 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 2 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 78fe 0 0000 3f 01 eb89 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 3 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 14b8 0 0000 3f 01 4fd0 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 4 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 8ef7 0 0000 3f 01 d590 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 5 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 ec9d 0 0000 3f 01 77ea 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 6 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 70e6 0 0000 3f 01 f3a1 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 7 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 b0d2 0 0000 3f 01 b3b5 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 8 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 f8b4 0 0000 3f 01 6bd3 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 9 Request timeout for icmp_seq 10 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 1c95 0 0000 3f 01 47f3 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 11 Request timeout for icmp_seq 12 Request timeout for icmp_seq 13 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 62bc 0 0000 3f 01 01cc 10.1.2.20 10.1.1.12 Why does this happen? From what I've read the Redirect Host response has something to do with the fact that the two hosts are in the same network and there being a shorter route (or so I understood). They are in fact in the same physical network, but why would there be a better route if they are not on the same subnet (they can't see each other)? What am I missing? Some extra info you might want to see: # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.8.0.2 0.0.0.0 255.255.255.255 UH 0 0 0 tun0 127.0.0.1 0.0.0.0 255.255.255.255 UH 0 0 0 lo 192.168.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth3 10.8.0.0 10.8.0.2 255.255.255.0 UG 0 0 0 tun0 192.168.1.0 0.0.0.0 255.255.255.0 U 1 0 0 eth2 10.1.4.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.1.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.1.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.1.3.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth2 0.0.0.0 192.168.2.1 0.0.0.0 UG 100 0 0 eth3 # iptables -L -n Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination # iptables -L -n -t nat Chain PREROUTING (policy ACCEPT) target prot opt source destination Chain POSTROUTING (policy ACCEPT) target prot opt source destination MASQUERADE all -- !10.0.0.0/8 10.0.0.0/8 MASQUERADE all -- 10.0.0.0/8 !10.0.0.0/8 Chain OUTPUT (policy ACCEPT) target prot opt source destination

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Announcing release of ASP.NET MVC 3, IIS Express, SQL CE 4, Web Farm Framework, Orchard, WebMatrix

- by ScottGu

I’m excited to announce the release today of several products: ASP.NET MVC 3 NuGet IIS Express 7.5 SQL Server Compact Edition 4 Web Deploy and Web Farm Framework 2.0 Orchard 1.0 WebMatrix 1.0 The above products are all free. They build upon the .NET 4 and VS 2010 release, and add a ton of additional value to ASP.NET (both Web Forms and MVC) and the Microsoft Web Server stack. ASP.NET MVC 3 Today we are shipping the final release of ASP.NET MVC 3. You can download and install ASP.NET MVC 3 here. The ASP.NET MVC 3 source code (released under an OSI-compliant open source license) can also optionally be downloaded here. ASP.NET MVC 3 is a significant update that brings with it a bunch of great features. Some of the improvements include: Razor ASP.NET MVC 3 ships with a new view-engine option called “Razor” (in addition to continuing to support/enhance the existing .aspx view engine). Razor minimizes the number of characters and keystrokes required when writing a view template, and enables a fast, fluid coding workflow. Unlike most template syntaxes, with Razor you do not need to interrupt your coding to explicitly denote the start and end of server blocks within your HTML. The Razor parser is smart enough to infer this from your code. This enables a compact and expressive syntax which is clean, fast and fun to type. You can learn more about Razor from some of the blog posts I’ve done about it over the last 6 months Introducing Razor New @model keyword in Razor Layouts with Razor Server-Side Comments with Razor Razor’s @: and <text> syntax Implicit and Explicit code nuggets with Razor Layouts and Sections with Razor Today’s release supports full code intellisense support for Razor (both VB and C#) with Visual Studio 2010 and the free Visual Web Developer 2010 Express. JavaScript Improvements ASP.NET MVC 3 enables richer JavaScript scenarios and takes advantage of emerging HTML5 capabilities. The AJAX and Validation helpers in ASP.NET MVC 3 now use an Unobtrusive JavaScript based approach. Unobtrusive JavaScript avoids injecting inline JavaScript into HTML, and enables cleaner separation of behavior using the new HTML 5 “data-“ attribute convention (which conveniently works on older browsers as well – including IE6). This keeps your HTML tight and clean, and makes it easier to optionally swap out or customize JS libraries. ASP.NET MVC 3 now includes built-in support for posting JSON-based parameters from client-side JavaScript to action methods on the server. This makes it easier to exchange data across the client and server, and build rich JavaScript front-ends. We think this capability will be particularly useful going forward with scenarios involving client templates and data binding (including the jQuery plugins the ASP.NET team recently contributed to the jQuery project). Previous releases of ASP.NET MVC included the core jQuery library. ASP.NET MVC 3 also now ships the jQuery Validate plugin (which our validation helpers use for client-side validation scenarios). We are also now shipping and including jQuery UI by default as well (which provides a rich set of client-side JavaScript UI widgets for you to use within projects). Improved Validation ASP.NET MVC 3 includes a bunch of validation enhancements that make it even easier to work with data. Client-side validation is now enabled by default with ASP.NET MVC 3 (using an onbtrusive javascript implementation). Today’s release also includes built-in support for Remote Validation - which enables you to annotate a model class with a validation attribute that causes ASP.NET MVC to perform a remote validation call to a server method when validating input on the client. The validation features introduced within .NET 4’s System.ComponentModel.DataAnnotations namespace are now supported by ASP.NET MVC 3. This includes support for the new IValidatableObject interface – which enables you to perform model-level validation, and allows you to provide validation error messages specific to the state of the overall model, or between two properties within the model. ASP.NET MVC 3 also supports the improvements made to the ValidationAttribute class in .NET 4. ValidationAttribute now supports a new IsValid overload that provides more information about the current validation context, such as what object is being validated. This enables richer scenarios where you can validate the current value based on another property of the model. We’ve shipped a built-in [Compare] validation attribute with ASP.NET MVC 3 that uses this support and makes it easy out of the box to compare and validate two property values. You can use any data access API or technology with ASP.NET MVC. This past year, though, we’ve worked closely with the .NET data team to ensure that the new EF Code First library works really well for ASP.NET MVC applications. These two posts of mine cover the latest EF Code First preview and demonstrates how to use it with ASP.NET MVC 3 to enable easy editing of data (with end to end client+server validation support). The final release of EF Code First will ship in the next few weeks. Today we are also publishing the first preview of a new MvcScaffolding project. It enables you to easily scaffold ASP.NET MVC 3 Controllers and Views, and works great with EF Code-First (and is pluggable to support other data providers). You can learn more about it – and install it via NuGet today - from Steve Sanderson’s MvcScaffolding blog post. Output Caching Previous releases of ASP.NET MVC supported output caching content at a URL or action-method level. With ASP.NET MVC V3 we are also enabling support for partial page output caching – which allows you to easily output cache regions or fragments of a response as opposed to the entire thing. This ends up being super useful in a lot of scenarios, and enables you to dramatically reduce the work your application does on the server. The new partial page output caching support in ASP.NET MVC 3 enables you to easily re-use cached sub-regions/fragments of a page across multiple URLs on a site. It supports the ability to cache the content either on the web-server, or optionally cache it within a distributed cache server like Windows Server AppFabric or memcached. I’ll post some tutorials on my blog that show how to take advantage of ASP.NET MVC 3’s new output caching support for partial page scenarios in the future. Better Dependency Injection ASP.NET MVC 3 provides better support for applying Dependency Injection (DI) and integrating with Dependency Injection/IOC containers. With ASP.NET MVC 3 you no longer need to author custom ControllerFactory classes in order to enable DI with Controllers. You can instead just register a Dependency Injection framework with ASP.NET MVC 3 and it will resolve dependencies not only for Controllers, but also for Views, Action Filters, Model Binders, Value Providers, Validation Providers, and Model Metadata Providers that you use within your application. This makes it much easier to cleanly integrate dependency injection within your projects. Other Goodies ASP.NET MVC 3 includes dozens of other nice improvements that help to both reduce the amount of code you write, and make the code you do write cleaner. Here are just a few examples: Improved New Project dialog that makes it easy to start new ASP.NET MVC 3 projects from templates. Improved Add->View Scaffolding support that enables the generation of even cleaner view templates. New ViewBag property that uses .NET 4’s dynamic support to make it easy to pass late-bound data from Controllers to Views. Global Filters support that allows specifying cross-cutting filter attributes (like [HandleError]) across all Controllers within an app. New [AllowHtml] attribute that allows for more granular request validation when binding form posted data to models. Sessionless controller support that allows fine grained control over whether SessionState is enabled on a Controller. New ActionResult types like HttpNotFoundResult and RedirectPermanent for common HTTP scenarios. New Html.Raw() helper to indicate that output should not be HTML encoded. New Crypto helpers for salting and hashing passwords. And much, much more… Learn More about ASP.NET MVC 3 We will be posting lots of tutorials and samples on the http://asp.net/mvc site in the weeks ahead. Below are two good ASP.NET MVC 3 tutorials available on the site today: Build your First ASP.NET MVC 3 Application: VB and C# Building the ASP.NET MVC 3 Music Store We’ll post additional ASP.NET MVC 3 tutorials and videos on the http://asp.net/mvc site in the future. Visit it regularly to find new tutorials as they are published. How to Upgrade Existing Projects ASP.NET MVC 3 is compatible with ASP.NET MVC 2 – which means it should be easy to update existing MVC projects to ASP.NET MVC 3. The new features in ASP.NET MVC 3 build on top of the foundational work we’ve already done with the MVC 1 and MVC 2 releases – which means that the skills, knowledge, libraries, and books you’ve acquired are all directly applicable with the MVC 3 release. MVC 3 adds new features and capabilities – it doesn’t obsolete existing ones. You can upgrade existing ASP.NET MVC 2 projects by following the manual upgrade steps in the release notes. Alternatively, you can use this automated ASP.NET MVC 3 upgrade tool to easily update your existing projects. Localized Builds Today’s ASP.NET MVC 3 release is available in English. We will be releasing localized versions of ASP.NET MVC 3 (in 9 languages) in a few days. I’ll blog pointers to the localized downloads once they are available. NuGet Today we are also shipping NuGet – a free, open source, package manager that makes it easy for you to find, install, and use open source libraries in your projects. It works with all .NET project types (including ASP.NET Web Forms, ASP.NET MVC, WPF, WinForms, Silverlight, and Class Libraries). You can download and install it here. NuGet enables developers who maintain open source projects (for example, .NET projects like Moq, NHibernate, Ninject, StructureMap, NUnit, Windsor, Raven, Elmah, etc) to package up their libraries and register them with an online gallery/catalog that is searchable. The client-side NuGet tools – which include full Visual Studio integration – make it trivial for any .NET developer who wants to use one of these libraries to easily find and install it within the project they are working on. NuGet handles dependency management between libraries (for example: library1 depends on library2). It also makes it easy to update (and optionally remove) libraries from your projects later. It supports updating web.config files (if a package needs configuration settings). It also allows packages to add PowerShell scripts to a project (for example: scaffold commands). Importantly, NuGet is transparent and clean – and does not install anything at the system level. Instead it is focused on making it easy to manage libraries you use with your projects. Our goal with NuGet is to make it as simple as possible to integrate open source libraries within .NET projects. NuGet Gallery This week we also launched a beta version of the http://nuget.org web-site – which allows anyone to easily search and browse an online gallery of open source packages available via NuGet. The site also now allows developers to optionally submit new packages that they wish to share with others. You can learn more about how to create and share a package here. There are hundreds of open-source .NET projects already within the NuGet Gallery today. We hope to have thousands there in the future. IIS Express 7.5 Today we are also shipping IIS Express 7.5. IIS Express is a free version of IIS 7.5 that is optimized for developer scenarios. It works for both ASP.NET Web Forms and ASP.NET MVC project types. We think IIS Express combines the ease of use of the ASP.NET Web Server (aka Cassini) currently built-into Visual Studio today with the full power of IIS. Specifically: It’s lightweight and easy to install (less than 5Mb download and a quick install) It does not require an administrator account to run/debug applications from Visual Studio It enables a full web-server feature set – including SSL, URL Rewrite, and other IIS 7.x modules It supports and enables the same extensibility model and web.config file settings that IIS 7.x support It can be installed side-by-side with the full IIS web server as well as the ASP.NET Development Server (they do not conflict at all) It works on Windows XP and higher operating systems – giving you a full IIS 7.x developer feature-set on all Windows OS platforms IIS Express (like the ASP.NET Development Server) can be quickly launched to run a site from a directory on disk. It does not require any registration/configuration steps. This makes it really easy to launch and run for development scenarios. You can also optionally redistribute IIS Express with your own applications if you want a lightweight web-server. The standard IIS Express EULA now includes redistributable rights. Visual Studio 2010 SP1 adds support for IIS Express. Read my VS 2010 SP1 and IIS Express blog post to learn more about what it enables. SQL Server Compact Edition 4 Today we are also shipping SQL Server Compact Edition 4 (aka SQL CE 4). SQL CE is a free, embedded, database engine that enables easy database storage. No Database Installation Required SQL CE does not require you to run a setup or install a database server in order to use it. You can simply copy the SQL CE binaries into the \bin directory of your ASP.NET application, and then your web application can use it as a database engine. No setup or extra security permissions are required for it to run. You do not need to have an administrator account on the machine. Just copy your web application onto any server and it will work. This is true even of medium-trust applications running in a web hosting environment. SQL CE runs in-memory within your ASP.NET application and will start-up when you first access a SQL CE database, and will automatically shutdown when your application is unloaded. SQL CE databases are stored as files that live within the \App_Data folder of your ASP.NET Applications. Works with Existing Data APIs SQL CE 4 works with existing .NET-based data APIs, and supports a SQL Server compatible query syntax. This means you can use existing data APIs like ADO.NET, as well as use higher-level ORMs like Entity Framework and NHibernate with SQL CE. This enables you to use the same data programming skills and data APIs you know today. Supports Development, Testing and Production Scenarios SQL CE can be used for development scenarios, testing scenarios, and light production usage scenarios. With the SQL CE 4 release we’ve done the engineering work to ensure that SQL CE won’t crash or deadlock when used in a multi-threaded server scenario (like ASP.NET). This is a big change from previous releases of SQL CE – which were designed for client-only scenarios and which explicitly blocked running in web-server environments. Starting with SQL CE 4 you can use it in a web-server as well. There are no license restrictions with SQL CE. It is also totally free. Tooling Support with VS 2010 SP1 Visual Studio 2010 SP1 adds support for SQL CE 4 and ASP.NET Projects. Read my VS 2010 SP1 and SQL CE 4 blog post to learn more about what it enables. Web Deploy and Web Farm Framework 2.0 Today we are also releasing Microsoft Web Deploy V2 and Microsoft Web Farm Framework V2. These services provide a flexible and powerful way to deploy ASP.NET applications onto either a single server, or across a web farm of machines. You can learn more about these capabilities from my previous blog posts on them: Introducing the Microsoft Web Farm Framework Automating Deployment with Microsoft Web Deploy Visit the http://iis.net website to learn more and install them. Both are free. Orchard 1.0 Today we are also releasing Orchard v1.0. Orchard is a free, open source, community based project. It provides Content Management System (CMS) and Blogging System support out of the box, and makes it possible to easily create and manage web-sites without having to write code (site owners can customize a site through the browser-based editing tools built-into Orchard). Read these tutorials to learn more about how you can setup and manage your own Orchard site. Orchard itself is built as an ASP.NET MVC 3 application using Razor view templates (and by default uses SQL CE 4 for data storage). Developers wishing to extend an Orchard site with custom functionality can open and edit it as a Visual Studio project – and add new ASP.NET MVC Controllers/Views to it. WebMatrix 1.0 WebMatrix is a new, free, web development tool from Microsoft that provides a suite of technologies that make it easier to enable website development. It enables a developer to start a new site by browsing and downloading an app template from an online gallery of web applications (which includes popular apps like Umbraco, DotNetNuke, Orchard, WordPress, Drupal and Joomla). Alternatively it also enables developers to create and code web sites from scratch. WebMatrix is task focused and helps guide developers as they work on sites. WebMatrix includes IIS Express, SQL CE 4, and ASP.NET - providing an integrated web-server, database and programming framework combination. It also includes built-in web publishing support which makes it easy to find and deploy sites to web hosting providers. You can learn more about WebMatrix from my Introducing WebMatrix blog post this summer. Visit http://microsoft.com/web to download and install it today. Summary I’m really excited about today’s releases – they provide a bunch of additional value that makes web development with ASP.NET, Visual Studio and the Microsoft Web Server a lot better. A lot of folks worked hard to share this with you today. On behalf of my whole team – we hope you enjoy them! Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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Capturing and Transforming ASP.NET Output with Response.Filter

- by Rick Strahl

During one of my Handlers and Modules session at DevConnections this week one of the attendees asked a question that I didn’t have an immediate answer for. Basically he wanted to capture response output completely and then apply some filtering to the output – effectively injecting some additional content into the page AFTER the page had completely rendered. Specifically the output should be captured from anywhere – not just a page and have this code injected into the page. Some time ago I posted some code that allows you to capture ASP.NET Page output by overriding the Render() method, capturing the HtmlTextWriter() and reading its content, modifying the rendered data as text then writing it back out. I’ve actually used this approach on a few occasions and it works fine for ASP.NET pages. But this obviously won’t work outside of the Page class environment and it’s not really generic – you have to create a custom page class in order to handle the output capture. [updated 11/16/2009 – updated ResponseFilterStream implementation and a few additional notes based on comments] Enter Response.Filter However, ASP.NET includes a Response.Filter which can be used – well to filter output. Basically Response.Filter is a stream through which the OutputStream is piped back to the Web Server (indirectly). As content is written into the Response object, the filter stream receives the appropriate Stream commands like Write, Flush and Close as well as read operations although for a Response.Filter that’s uncommon to be hit. The Response.Filter can be programmatically replaced at runtime which allows you to effectively intercept all output generation that runs through ASP.NET. A common Example: Dynamic GZip Encoding A rather common use of Response.Filter hooking up code based, dynamic GZip compression for requests which is dead simple by applying a GZipStream (or DeflateStream) to Response.Filter. The following generic routines can be used very easily to detect GZip capability of the client and compress response output with a single line of code and a couple of library helper routines: WebUtils.GZipEncodePage(); which is handled with a few lines of reusable code and a couple of static helper methods: /// <summary> ///Sets up the current page or handler to use GZip through a Response.Filter ///IMPORTANT: ///You have to call this method before any output is generated! /// </summary> public static void GZipEncodePage() { HttpResponse Response = HttpContext.Current.Response; if(IsGZipSupported()) { stringAcceptEncoding = HttpContext.Current.Request.Headers["Accept-Encoding"]; if(AcceptEncoding.Contains("deflate")) { Response.Filter = newSystem.IO.Compression.DeflateStream(Response.Filter, System.IO.Compression.CompressionMode.Compress); Response.AppendHeader("Content-Encoding", "deflate"); } else { Response.Filter = newSystem.IO.Compression.GZipStream(Response.Filter, System.IO.Compression.CompressionMode.Compress); Response.AppendHeader("Content-Encoding", "gzip"); } } // Allow proxy servers to cache encoded and unencoded versions separately Response.AppendHeader("Vary", "Content-Encoding"); } /// <summary> /// Determines if GZip is supported /// </summary> /// <returns></returns> public static bool IsGZipSupported() { string AcceptEncoding = HttpContext.Current.Request.Headers["Accept-Encoding"]; if (!string.IsNullOrEmpty(AcceptEncoding) && (AcceptEncoding.Contains("gzip") || AcceptEncoding.Contains("deflate"))) return true; return false; } GZipStream and DeflateStream are streams that are assigned to Response.Filter and by doing so apply the appropriate compression on the active Response. Response.Filter content is chunked So to implement a Response.Filter effectively requires only that you implement a custom stream and handle the Write() method to capture Response output as it’s written. At first blush this seems very simple – you capture the output in Write, transform it and write out the transformed content in one pass. And that indeed works for small amounts of content. But you see, the problem is that output is written in small buffer chunks (a little less than 16k it appears) rather than just a single Write() statement into the stream, which makes perfect sense for ASP.NET to stream data back to IIS in smaller chunks to minimize memory usage en route. Unfortunately this also makes it a more difficult to implement any filtering routines since you don’t directly get access to all of the response content which is problematic especially if those filtering routines require you to look at the ENTIRE response in order to transform or capture the output as is needed for the solution the gentleman in my session asked for. So in order to address this a slightly different approach is required that basically captures all the Write() buffers passed into a cached stream and then making the stream available only when it’s complete and ready to be flushed. As I was thinking about the implementation I also started thinking about the few instances when I’ve used Response.Filter implementations. Each time I had to create a new Stream subclass and create my custom functionality but in the end each implementation did the same thing – capturing output and transforming it. I thought there should be an easier way to do this by creating a re-usable Stream class that can handle stream transformations that are common to Response.Filter implementations. Creating a semi-generic Response Filter Stream Class What I ended up with is a ResponseFilterStream class that provides a handful of Events that allow you to capture and/or transform Response content. The class implements a subclass of Stream and then overrides Write() and Flush() to handle capturing and transformation operations. By exposing events it’s easy to hook up capture or transformation operations via single focused methods. ResponseFilterStream exposes the following events: CaptureStream, CaptureString Captures the output only and provides either a MemoryStream or String with the final page output. Capture is hooked to the Flush() operation of the stream. TransformStream, TransformString Allows you to transform the complete response output with events that receive a MemoryStream or String respectively and can you modify the output then return it back as a return value. The transformed output is then written back out in a single chunk to the response output stream. These events capture all output internally first then write the entire buffer into the response. TransformWrite, TransformWriteString Allows you to transform the Response data as it is written in its original chunk size in the Stream’s Write() method. Unlike TransformStream/TransformString which operate on the complete output, these events only see the current chunk of data written. This is more efficient as there’s no caching involved, but can cause problems due to searched content splitting over multiple chunks. Using this implementation, creating a custom Response.Filter transformation becomes as simple as the following code. To hook up the Response.Filter using the MemoryStream version event: ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformStream += filter_TransformStream; Response.Filter = filter; and the event handler to do the transformation: MemoryStream filter_TransformStream(MemoryStream ms) { Encoding encoding = HttpContext.Current.Response.ContentEncoding; string output = encoding.GetString(ms.ToArray()); output = FixPaths(output); ms = new MemoryStream(output.Length); byte[] buffer = encoding.GetBytes(output); ms.Write(buffer,0,buffer.Length); return ms; } private string FixPaths(string output) { string path = HttpContext.Current.Request.ApplicationPath; // override root path wonkiness if (path == "/") path = ""; output = output.Replace("\"~/", "\"" + path + "/").Replace("'~/", "'" + path + "/"); return output; } The idea of the event handler is that you can do whatever you want to the stream and return back a stream – either the same one that’s been modified or a brand new one – which is then sent back to as the final response. The above code can be simplified even more by using the string version events which handle the stream to string conversions for you: ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformString += filter_TransformString; Response.Filter = filter; and the event handler to do the transformation calling the same FixPaths method shown above: string filter_TransformString(string output) { return FixPaths(output); } The events for capturing output and capturing and transforming chunks work in a very similar way. By using events to handle the transformations ResponseFilterStream becomes a reusable component and we don’t have to create a new stream class or subclass an existing Stream based classed. By the way, the example used here is kind of a cool trick which transforms “~/” expressions inside of the final generated HTML output – even in plain HTML controls not HTML controls – and transforms them into the appropriate application relative path in the same way that ResolveUrl would do. So you can write plain old HTML like this: <a href=”~/default.aspx”>Home</a> and have it turned into: <a href=”/myVirtual/default.aspx”>Home</a> without having to use an ASP.NET control like Hyperlink or Image or having to constantly use: <img src=”<%= ResolveUrl(“~/images/home.gif”) %>” /> in MVC applications (which frankly is one of the most annoying things about MVC especially given the path hell that extension-less and endpoint-less URLs impose). I can’t take credit for this idea. While discussing the Response.Filter issues on Twitter a hint from Dylan Beattie who pointed me at one of his examples which does something similar. I thought the idea was cool enough to use an example for future demos of Response.Filter functionality in ASP.NET next I time I do the Modules and Handlers talk (which was great fun BTW). How practical this is is debatable however since there’s definitely some overhead to using a Response.Filter in general and especially on one that caches the output and the re-writes it later. Make sure to test for performance anytime you use Response.Filter hookup and make sure it' doesn’t end up killing perf on you. You’ve been warned :-}. How does ResponseFilterStream work? The big win of this implementation IMHO is that it’s a reusable component – so for implementation there’s no new class, no subclassing – you simply attach to an event to implement an event handler method with a straight forward signature to retrieve the stream or string you’re interested in. The implementation is based on a subclass of Stream as is required in order to handle the Response.Filter requirements. What’s different than other implementations I’ve seen in various places is that it supports capturing output as a whole to allow retrieving the full response output for capture or modification. The exception are the TransformWrite and TransformWrite events which operate only active chunk of data written by the Response. For captured output, the Write() method captures output into an internal MemoryStream that is cached until writing is complete. So Write() is called when ASP.NET writes to the Response stream, but the filter doesn’t pass on the Write immediately to the filter’s internal stream. The data is cached and only when the Flush() method is called to finalize the Stream’s output do we actually send the cached stream off for transformation (if the events are hooked up) and THEN finally write out the returned content in one big chunk. Here’s the implementation of ResponseFilterStream: /// <summary> /// A semi-generic Stream implementation for Response.Filter with /// an event interface for handling Content transformations via /// Stream or String. /// <remarks> /// Use with care for large output as this implementation copies /// the output into a memory stream and so increases memory usage. /// </remarks> /// </summary> public class ResponseFilterStream : Stream { /// <summary> /// The original stream /// </summary> Stream _stream; /// <summary> /// Current position in the original stream /// </summary> long _position; /// <summary> /// Stream that original content is read into /// and then passed to TransformStream function /// </summary> MemoryStream _cacheStream = new MemoryStream(5000); /// <summary> /// Internal pointer that that keeps track of the size /// of the cacheStream /// </summary> int _cachePointer = 0; /// <summary> /// /// </summary> /// <param name="responseStream"></param> public ResponseFilterStream(Stream responseStream) { _stream = responseStream; } /// <summary> /// Determines whether the stream is captured /// </summary> private bool IsCaptured { get { if (CaptureStream != null || CaptureString != null || TransformStream != null || TransformString != null) return true; return false; } } /// <summary> /// Determines whether the Write method is outputting data immediately /// or delaying output until Flush() is fired. /// </summary> private bool IsOutputDelayed { get { if (TransformStream != null || TransformString != null) return true; return false; } } /// <summary> /// Event that captures Response output and makes it available /// as a MemoryStream instance. Output is captured but won't /// affect Response output. /// </summary> public event Action<MemoryStream> CaptureStream; /// <summary> /// Event that captures Response output and makes it available /// as a string. Output is captured but won't affect Response output. /// </summary> public event Action<string> CaptureString; /// <summary> /// Event that allows you transform the stream as each chunk of /// the output is written in the Write() operation of the stream. /// This means that that it's possible/likely that the input /// buffer will not contain the full response output but only /// one of potentially many chunks. /// /// This event is called as part of the filter stream's Write() /// operation. /// </summary> public event Func<byte[], byte[]> TransformWrite; /// <summary> /// Event that allows you to transform the response stream as /// each chunk of bytep[] output is written during the stream's write /// operation. This means it's possibly/likely that the string /// passed to the handler only contains a portion of the full /// output. Typical buffer chunks are around 16k a piece. /// /// This event is called as part of the stream's Write operation. /// </summary> public event Func<string, string> TransformWriteString; /// <summary> /// This event allows capturing and transformation of the entire /// output stream by caching all write operations and delaying final /// response output until Flush() is called on the stream. /// </summary> public event Func<MemoryStream, MemoryStream> TransformStream; /// <summary> /// Event that can be hooked up to handle Response.Filter /// Transformation. Passed a string that you can modify and /// return back as a return value. The modified content /// will become the final output. /// </summary> public event Func<string, string> TransformString; protected virtual void OnCaptureStream(MemoryStream ms) { if (CaptureStream != null) CaptureStream(ms); } private void OnCaptureStringInternal(MemoryStream ms) { if (CaptureString != null) { string content = HttpContext.Current.Response.ContentEncoding.GetString(ms.ToArray()); OnCaptureString(content); } } protected virtual void OnCaptureString(string output) { if (CaptureString != null) CaptureString(output); } protected virtual byte[] OnTransformWrite(byte[] buffer) { if (TransformWrite != null) return TransformWrite(buffer); return buffer; } private byte[] OnTransformWriteStringInternal(byte[] buffer) { Encoding encoding = HttpContext.Current.Response.ContentEncoding; string output = OnTransformWriteString(encoding.GetString(buffer)); return encoding.GetBytes(output); } private string OnTransformWriteString(string value) { if (TransformWriteString != null) return TransformWriteString(value); return value; } protected virtual MemoryStream OnTransformCompleteStream(MemoryStream ms) { if (TransformStream != null) return TransformStream(ms); return ms; } /// <summary> /// Allows transforming of strings /// /// Note this handler is internal and not meant to be overridden /// as the TransformString Event has to be hooked up in order /// for this handler to even fire to avoid the overhead of string /// conversion on every pass through. /// </summary> /// <param name="responseText"></param> /// <returns></returns> private string OnTransformCompleteString(string responseText) { if (TransformString != null) TransformString(responseText); return responseText; } /// <summary> /// Wrapper method form OnTransformString that handles /// stream to string and vice versa conversions /// </summary> /// <param name="ms"></param> /// <returns></returns> internal MemoryStream OnTransformCompleteStringInternal(MemoryStream ms) { if (TransformString == null) return ms; //string content = ms.GetAsString(); string content = HttpContext.Current.Response.ContentEncoding.GetString(ms.ToArray()); content = TransformString(content); byte[] buffer = HttpContext.Current.Response.ContentEncoding.GetBytes(content); ms = new MemoryStream(); ms.Write(buffer, 0, buffer.Length); //ms.WriteString(content); return ms; } /// <summary> /// /// </summary> public override bool CanRead { get { return true; } } public override bool CanSeek { get { return true; } } /// <summary> /// /// </summary> public override bool CanWrite { get { return true; } } /// <summary> /// /// </summary> public override long Length { get { return 0; } } /// <summary> /// /// </summary> public override long Position { get { return _position; } set { _position = value; } } /// <summary> /// /// </summary> /// <param name="offset"></param> /// <param name="direction"></param> /// <returns></returns> public override long Seek(long offset, System.IO.SeekOrigin direction) { return _stream.Seek(offset, direction); } /// <summary> /// /// </summary> /// <param name="length"></param> public override void SetLength(long length) { _stream.SetLength(length); } /// <summary> /// /// </summary> public override void Close() { _stream.Close(); } /// <summary> /// Override flush by writing out the cached stream data /// </summary> public override void Flush() { if (IsCaptured && _cacheStream.Length > 0) { // Check for transform implementations _cacheStream = OnTransformCompleteStream(_cacheStream); _cacheStream = OnTransformCompleteStringInternal(_cacheStream); OnCaptureStream(_cacheStream); OnCaptureStringInternal(_cacheStream); // write the stream back out if output was delayed if (IsOutputDelayed) _stream.Write(_cacheStream.ToArray(), 0, (int)_cacheStream.Length); // Clear the cache once we've written it out _cacheStream.SetLength(0); } // default flush behavior _stream.Flush(); } /// <summary> /// /// </summary> /// <param name="buffer"></param> /// <param name="offset"></param> /// <param name="count"></param> /// <returns></returns> public override int Read(byte[] buffer, int offset, int count) { return _stream.Read(buffer, offset, count); } /// <summary> /// Overriden to capture output written by ASP.NET and captured /// into a cached stream that is written out later when Flush() /// is called. /// </summary> /// <param name="buffer"></param> /// <param name="offset"></param> /// <param name="count"></param> public override void Write(byte[] buffer, int offset, int count) { if ( IsCaptured ) { // copy to holding buffer only - we'll write out later _cacheStream.Write(buffer, 0, count); _cachePointer += count; } // just transform this buffer if (TransformWrite != null) buffer = OnTransformWrite(buffer); if (TransformWriteString != null) buffer = OnTransformWriteStringInternal(buffer); if (!IsOutputDelayed) _stream.Write(buffer, offset, buffer.Length); } } The key features are the events and corresponding OnXXX methods that handle the event hookups, and the Write() and Flush() methods of the stream implementation. All the rest of the members tend to be plain jane passthrough stream implementation code without much consequence. I do love the way Action<t> and Func<T> make it so easy to create the event signatures for the various events – sweet. A few Things to consider Performance Response.Filter is not great for performance in general as it adds another layer of indirection to the ASP.NET output pipeline, and this implementation in particular adds a memory hit as it basically duplicates the response output into the cached memory stream which is necessary since you may have to look at the entire response. If you have large pages in particular this can cause potentially serious memory pressure in your server application. So be careful of wholesale adoption of this (or other) Response.Filters. Make sure to do some performance testing to ensure it’s not killing your app’s performance. Response.Filter works everywhere A few questions came up in comments and discussion as to capturing ALL output hitting the site and – yes you can definitely do that by assigning a Response.Filter inside of a module. If you do this however you’ll want to be very careful and decide which content you actually want to capture especially in IIS 7 which passes ALL content – including static images/CSS etc. through the ASP.NET pipeline. So it is important to filter only on what you’re looking for – like the page extension or maybe more effectively the Response.ContentType. Response.Filter Chaining Originally I thought that filter chaining doesn’t work at all due to a bug in the stream implementation code. But it’s quite possible to assign multiple filters to the Response.Filter property. So the following actually works to both compress the output and apply the transformed content: WebUtils.GZipEncodePage(); ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformString += filter_TransformString; Response.Filter = filter; However the following does not work resulting in invalid content encoding errors: ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformString += filter_TransformString; Response.Filter = filter; WebUtils.GZipEncodePage(); In other words multiple Response filters can work together but it depends entirely on the implementation whether they can be chained or in which order they can be chained. In this case running the GZip/Deflate stream filters apparently relies on the original content length of the output and chokes when the content is modified. But if attaching the compression first it works fine as unintuitive as that may seem. Resources Download example code Capture Output from ASP.NET Pages © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET

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IIS SSL Certificate Renewal Pain

- by Rick Strahl

I’m in the middle of my annual certificate renewal for the West Wind site and I can honestly say that I hate IIS’s certificate system. When it works it’s fine, but when it doesn’t man can it be a pain. Because I deal with public certificates on my site merely once a year, and you have to perform the certificate dance just the right way, I seem to run into some sort of trouble every year, thinking that Microsoft surely must have addressed the issues I ran into previously – HA! Not so. Don’t ever use the Renew Certificate Feature in IIS! The first rule that I should have never forgotten is that certificate renewals in IIS (7 is what I’m using but I think it’s no different in 7.5 and 8), simply don’t work if you’re submitting to get a public certificate from a certificate authority. I use DNSimple for my DNS domain management and SSL certificates because they provide ridiculously easy domain management and good prices for SSL certs – especially wildcard certificates, which is what I use on west-wind.com. Certificates in IIS can be found pegged to the machine root. If you go into the IIS Manager, go to the machine root the tree and then click on certificates and you then get various certificate options: Both of these options create a new Certificate request (CSR), which is just a text file. But if you’re silly enough like me to click on the Renew button on your old certificate, you’ll find that you end up generating a very long Certificate Request that looks nothing like the original certificate request and the format that’s used for this is not accepted by most certificate authorities. While I’m not sure exactly what the problem is, it simply looks like IIS is respecting none of your original certificate bit size choices and is generating a huge certificate request that is 3 times the size of a ‘normal’ certificate request. The end result is (and I’ve done this at least twice now) is that the certificate processor is likely to fail processing those renewals. Always create a new Certificate While it’s a little more work and you have to remember how to fill out the certificate request properly, this is the safe way to make sure your certificate generates properly. First comes the Distinguished Name Properties dialog: Ah yes you have to love the nomenclature of this stuff. Distinguished name, Common name – WTF is a common name? It doesn’t look common to me! Make sure this form gets filled out correctly. Common NameThis is the domain name of the Web site. In my case I’m creating a wildcard certificate so I’m using the * prefix. If you’re purchasing a certificate for a specific domain use www.west-wind.com or store.west-wind.com for example. Make sure this matches the EXACT domain you’re trying to use secure access on because that’s all the certificate is going to work on unless you get a wildcard certificate. Organization Is the name of your company or organization. Depending on the kind of certificate you purchase this name will show up on your certificate. Most low end SSL certificates (ie. those that cost under $100 for single domains) don’t list the organization, the higher signature certificates that also require extensive validation by the cert authority do. Regardless you should make sure this matches the right company/organization. Organizational Unit This can be anything. Not really sure what this is for, but traditionally I’ve always set this to Web because – well this is a Web thing after all right? I’ve never seen this used anywhere that I can tell other than to internally reference the cert. State and CountryPretty obvious. Should reflect the location of the business/organization/person or site. Next you have to configure the bit size used for the certificate: The default on this dialog is 1024, but I’ve found that most providers these days request a minimum bit length of 2048, as did my DNSimple provider. Again check with the provider when you submit to make sure. Bit length mismatches can cause problems if you use a size that isn’t supported by the provider. I had that happen last year when I submitted my CSR and it got rejected quite a bit later, when the certs usually are issued within an hour or less. When you’re done here, the certificate is saved to disk as a .txt file and it should look something like this (this is a 2048 bit length CSR):-----BEGIN NEW CERTIFICATE REQUEST----- MIIEVGCCAz0CAQAwdjELMAkGA1UEBhMCVVMxDzANBgNVBAgMBkhhd2FpaTENMAsG A1UEBwwEUGFpYTEfMB0GA1UECgwWV2VzdCBXaW5kIFRlY2hub2xvZ2llczEMMAoG B1UECwwDV2ViMRgwFgYDVQQDDA8qLndlc3Qtd2luZC5jb20wggEiMA0GCSqGSIb3 DQEBAQUAA4IBDwAwggEKAoIBAQDIPWOFMkMVRp2Ftj9w/cCVV4OYYhoZYtl+8lTk oqDwKca0xWHLgioX/9v0rZLS6a82MHqKEBxVXu+cuCmSE4AQtB/1YH9lS4tpc/be OZDvnTotP6l4MCEzzAfROcw4CiIg6X0RMSnl8IATAvv2V5LQM9TDdt9oDdMpX2IY +vVC9RZ7PMHBmR9kwI2i/lrKitzhQKaHgpmKcRlM6iqpALUiX28w5HJaDKK1MDHN 607tyFJLHijuJKx7PdTqZYf50KkC3NupfZ2avVycf18Q13jHWj59tvwEOczoVzRL l4LQivAqbhyiqMpWnrZunIOUZta5aGm+jo7O1knGWJjxuraTAgMBAAGgggGYMBoG CisGAQQBgjcNAgMxDBYKNi4yLjkyMDAuMjA0BgkrBgEEAYI3FRQxJzAlAgEFDAZS QVNYUFMMC1JBU1hQU1xSaWNrDAtJbmV0TWdyLmV4ZTByBgorBgEEAYI3DQICMWQw YgIBAR5aAE0AaQBjAHIAbwBzAG8AZgB0ACAAUgBTAEEAIABTAEMAaABhAG4AbgBl AGwAIABDAHIAeQBwAHQAbwBnAHIAYQBwAGgAaQBjACAAUAByAG8AdgBpAGQAZQBy AwEAMIHPBgkqhkiG9w0BCQ4xgcEwgb4wDgYDVR0PAQH/BAQDAgTwMBMGA1UdJQQM MAoGCCsGAQUFBwMBMHgGCSqGSIb3DQEJDwRrMGkwDgYIKoZIhvcNAwICAgCAMA4G CCqGSIb3DQMEAgIAgDALBglghkgBZQMEASowCwYJYIZIAWUDBAEtMAsGCWCGSAFl AwQBAjALBglghkgBZQMEAQUwBwYFKw4DAgcwCgYIKoZIhvcNAwcwHQYDVR0OBBYE FD/yOsTbXE+GVFCFMmldzQvyloz9MA0GCSqGSIb3DQEBBQUAA4IBAQCK6LlsCuIM 1AU0niB6QZ9v0FTsGFxP1dYvVUnJyY6VEKNiGFiQjZac7UCs0p58yScdXWEFOE8V OsjAYD3xYNc05+ckyD67UHRGEUAVB9RBvbKW23KeR/8kBmEzc8PemD52YOgExxAJ 57xWmAwEHAvbgYzQvhO8AOzH3TGvvHbg5UKM1pYgNmuwZq5DkL/IDoeIJwfk/wrI wghNTuxxIFgbH4YrgLgv4PRvrS/LaTCRBdboaCgzATMczaOb1nd/DVNR+3fCtMhM W0psTAjzRbmXF3nJyAQa7jF/52gkY0RfFX2lG5tJnG+XDsVNvKNvh9Qa5Tlmkm06 ILKCm9ciWCKk -----END NEW CERTIFICATE REQUEST----- You can take that certificate request and submit that to your certificate provider. Since this is base64 encoded you can typically just paste it into a text box on the submission page, or some providers will ask you to upload the CSR as a file. What does a Renewal look like? Note the length of the CSR will vary somewhat with key strength, but compare this to a renewal request that IIS generated from my existing site:-----BEGIN NEW CERTIFICATE REQUEST----- MIIPpwYFKoZIhvcNAQcCoIIPmDCCD5QCAQExCzAJBgUrDgMCGgUAMIIIqAYJKoZI hvcNAQcBoIIImQSCCJUwggiRMIIH+gIBADBdMSEwHwYDVQQLDBhEb21haW4gQ29u dHJvbCBWYWxpFGF0ZWQxHjAcBgNVBAsMFUVzc2VudGlhbFNTTCBXaWxkY2FyZDEY MBYGA1UEAwwPKi53ZXN0LXdpbmQuY29tMIGfMA0GCSqGSIb3DQEBAQUAA4GNADCB iQKBgQCK4OuIOR18Wb8tNMGRZiD1c9X57b332Lj7DhbckFqLs0ys8kVDHrTXSj+T Ye9nmAvfPpZmBtE5p9qRNN79rUYugAdl+qEtE4IJe1bRfxXzcKa1SXa8+TEs3zQa zYSmcR2dDuC8om1eAdeCtt0NnkvANgm1VLwGOor/UHMASaEhCQIDAQABoIIG8jAa BgorBgEEAYI3DQIDMQwWCjYuMi45MjAwLjIwNAYJKwYBBAGCNxUUMScwJQIBBQwG UkFTWFBTDAtSQVNYUFNcUmljawwLSW5ldE1nci5leGUwZgYKKwYBBAGCNw0CAjFY MFYCAQIeTgBNAGkAYwByAG8AcwBvAGYAdAAgAFMAdAByAG8AbgBnACAAQwByAHkA cAB0AG8AZwByAGEAcABoAGkAYwAgAFAAcgBvAHYAaQBkAGUAcgMBADCCAQAGCSqG SIb3DQEJDjGB8jCB7zAOBgNVHQ8BAf8EBAMCBaAwDAYDVR0TAQH/BAIwADA0BgNV 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+XZ8bhM7vsAS+pZionR4MyuQ0mYIt/lDcsZVZ91KxTsIm8rNMkkYGFoSIXjQ0+0t CbxMF0i2qnpmNRpA6PU8l7lxxvPkplsk9KB8QIPFrR5p/i/SUAd9vECWh5+/ktlc rfFP2PK7XcEwWizsvMrNqLyvQVNXSUPTMYIBrzCCAasCAQEwgYcwcjELMAkGA1UE BhMCR0IxGzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2Fs Zm9yZDEaMBgGA1UEChMRQ09NT0RPIENBIExpbWl0ZWQxGDAWBgNVBAMTD0Vzc2Vu dGlhbFNTTCBDQQIRAO7UTVPkm+2Sbks59IdptaUwCQYFKw4DAhoFADANBgkqhkiG 9w0BAQEFAASCAQB8PNQ6bYnQpWfkHyxnDuvNKw3wrqF2p7JMZm+SuN2qp3R2LpCR mW2LrGtQIm9Iob/QOYH+8houYNVdvsATGPXX2T8gzn+anof4tOG0vCTK1Bp9bwf9 MkRP+1c8RW/vkYmUW4X5/C+y3CZpMH5dDTaXBIpXFzjX/fxNpH/rvLzGiaYYL3Cn OLO+aOADr9qq5yoqwpiYCSfYNNYKTUNNGfYIidQwYtbHXEYhSukB2oR89xD2sZZ4 bOqFjUPgTa5SsERLDDeg3omMKiIXVYGxlqBEq51Kge6IQt4qQV9P9VgInW7cWmKe dTqNHI9ri3ttewdEnT++TKGKKfTjX9SR8Waj -----END NEW CERTIFICATE REQUEST----- Clearly there’s something very different between this an my original request! And it didn’t work. IIS creates a custom CSR that is encoded in a format that no certificate authority I’ve ever used uses. If you want the gory details of what’s in there look at this ServerFault question (thanks to Mika in the comments). In the end it doesn’t matter though – no certificate authority knows what to do with this CSR. So create a new CSR and skip the renewal. Always! Use the same Server Keep in mind that on IIS at least you should always create your certificate on a single server and then when you receive the final certificate from your provider import it on that server. IIS tracks the CSR it created and requires it in order to import the final certificate properly. So if for some reason you try to install the certificate on another server, it won’t work. I’ve also run into trouble trying to install the same certificate twice – this time around I didn’t give my certificate the proper friendly name and IIS failed to allow me to assign the certificate to any of my Web sites. So I removed the certificate and tried to import again, only to find it failed the second time around. There are other ways to fix this, but in my case I had to have the certificate re-issued to work – not what you want to do. Regardless of what you do though, when you import make sure you do it right the first time by crossing all your t’s and dotting your i's– it’ll save you a lot of grief! You don’t actually have to use the server that the certificate gets installed on to generate the CSR and first install it, but it is generally a good idea to do so just so you can get the certificate installed into the right place right away. If you have access to the server where you need to install the certificate you might as well use it. But you can use another machine to generated the and install the certificate, then export the certificate and move it to another machine as needed. So you can use your Dev machine to create a certificate then export it and install it on a live server. More on installation and back up/export later. Installing the Certificate Once you’ve submitted a CSR request your provider will process the request and eventually issue you a new final certificate that contains another text file with the final key to import into your certificate store. IIS does this by combining the content in your certificate request with the original CSR. If all goes well your new certificate shows up in the certificate list and you’re ready to assign the certificate to your sites. Make sure you use a friendly name that matches domain name of your site. So use *.mysite.com or www.mysite.com or store.mysite.com to ensure IIS recognizes the certificate. I made the mistake of not naming my friendly name this way and found that IIS was unable to link my sites to my wildcard certificate. It needed to have the *. as part of the certificate otherwise the Hostname input field was blanked out. Changing the Friendly Name If you by accidentally used an invalid friendly name you can change it later in the Windows certificate store. Bring up a Run Box Type MMC File | Add/Remove Snap In Add Certificates | Computer Account | Local Computer Drill into Certificates | Personal | Certificates Find your Certificate | Right Click | Properties Edit the Friendly Name | Click OK Backing up your Certificate The first thing you should do once your certificate is successfully installed is to back it up! In case your server crashes or you otherwise lose your configuration this will ensure you have an easy way to recover and reinstall your certificate either on the same server or a different one. If you’re running a server farm or using a wildcard certificate you also need to get the certificate onto other machines and a PFX file import is the easiest way to do this. To back up your certificate select your certificate and choose Export from the context or sidebar menu: The Export Certificate option allows you to export a password protected binary file that you can import in a single step. You can copy the resulting binary PFX file to back up or copy to other machines to install on. Importing the certificate on another machine is as easy as pointing at the PFX file and specifying the password. IIS handles the rest. Assigning a new certificate to your Site Once you have the new certificate installed, all that’s left to do is assign it to your site. In IIS select your Web site and bring up the Site Bindings from the right sidebar. Add a new binding for https, bind it to port 443, specify your hostname and pick the certificate from the pick list. If you’re using a root site make sure to set up your certificate for www.yoursite.com and also for yoursite.com so that both work properly with SSL. Note that you need to explicitly configure each hostname for a certificate if you plan to use SSL. Luckily if you update your SSL certificate in the following year, IIS prompts you and asks whether you like to update all other sites that are using the existing cert to the newer cert. And you’re done. So what’s the Pain? So, all of this is old hat and it doesn’t look all that bad right? So what’s the pain here? Well if you follow the instructions and do everything right, then the process is about as straight forward as you would expect it to be. You create a cert request, you import it and assign it to your sites. That’s the basic steps and to be perfectly fair it works well – if nothing goes wrong. However, renewing tends to be the problem. The first unintuitive issue is that you simply shouldn’t renew but create a new CSR and generate your new certificate from that. Over the years I’ve fallen prey to the belief that Microsoft eventually will fix this so that the renewal creates the same type of CSR as the old cert, but apparently that will just never happen. Booo! The other problem I ran into is that I accidentally misnamed my imported certificate which in turn set off a chain of events that caused my originally issued certificate to become uninstallable. When I received my completed certificate I installed it and it installed just fine, but the friendly name was wrong. As a result IIS refused to assign the certificate to any of my host headered sites. That’s strike number one. Why the heck should the friendly name have any effect on the ability to attach the certificate??? Next I uninstalled the certificate because I figured that would be the easiest way to make sure I get it right. But I found that I could not reinstall my certificate. I kept getting these stop errors: "ASN1 bad tag value met" that would prevent the installation from completion. After searching around for this error and reading countless long messages on forums, I found that this error supposedly does not actually mean the install failed, but the list wouldn’t refresh. Commodo has this to say: Note: There is a known issue in IIS 7 giving the following error: "Cannot find the certificate request associated with this certificate file. A certificate request must be completed on the computer where it was created." You may also receive a message stating "ASN1 bad tag value met". If this is the same server that you generated the CSR on then, in most cases, the certificate is actually installed. Simply cancel the dialog and press "F5" to refresh the list of server certificates. If the new certificate is now in the list, you can continue with the next step. If it is not in the list, you will need to reissue your certificate using a new CSR (see our CSR creation instructions for IIS 7). After creating a new CSR, login to your Comodo account and click the 'replace' button for your certificate. Not sure if this issue is fixed in IIS 8 but that’s an insane bug to have crop up. As it turns out, in my case the refresh didn’t work and the certificate didn’t show up in the IIS list after the reinstall. In fact when looking at the certificate store I could see my certificate was installed in the right place, but the private key is missing which is most likely why IIS is not picking it up. It looks like IIS could not match the final cert to the original CSR generated. But again some sort of message to that affect might be helpful instead of ASN1 bad tag value met. Recovering the Private Key So it turns out my original problem was that I received the published key, but when I imported the private key was missing. There’s a relatively easy way to recover from this. If your certificate doesn’t show up in IIS check in the certificate store for the local machine (see steps above on how to bring this up). If you look at the certificate in Certificates/Personal/Certificates make sure you see the key as shown in the image below: if the key is missing it means that the certificate is missing the private key most likely. To fix a certificate you can do the following: Double click the certificate Go to the Details Tab Copy down the Serial number You can copy the serial number from the area blurred out above. The serial number will be in a format like ?00 a7 9b a1 a4 9d 91 63 57 d6 9f 26 b8 ee 79 b5 cb and you’ll need to strip out the spaces in order to use it in the next step. Next open up an Administrative command prompt and issue the following command: certutil -repairstore my 00a79ba1a49d916357d69f26b8ee79b5cb You should get a confirmation message that the repair worked. If you now go back to the certificate store you should now see the key icon show up on the certificate. Your certificate is fixed. Now go back into IIS Manager and refresh the list of certificates and if all goes well you should see all the certificates that showed in the cert store now: Remember – back up the key first then map to your site… Summary I deal with a lot of customers who run their own IIS servers, and I can’t tell you how often I hear about botched SSL installations. When I posted some of my issues on Twitter yesterday I got a hell storm of “me too” responses. I’m clearly not the only one, who’s run into this especially with renewals. I feel pretty comfortable with IIS configuration and I do a lot of it for support purposes, but the SSL configuration is one that never seems to go seamlessly. This blog post is meant as reminder to myself to read next time I do a renewal. So I can dot my i's and dash my t’s before I get caught in the mess I’m dealing with today. Hopefully some of you find this useful as well.© Rick Strahl, West Wind Technologies, 2005-2014Posted in IIS7 Security Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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Another "Windows 7 entry missing from Grub2" Question

- by 4x10

Like many before me had the following problem that after installing Ubuntu (with windows 7 already installed), the grub boot loader wouldnt show windows 7 as a boot option, though i can boot fine if I use the "Choose Boot Device" options on the x220. The difference is that I try using UEFI only so many answers didn't really fit my problem, though i tried several stuffs: after running boot repair it destroyed the ubuntu boot loader custom entry in /etc/grub.d/40_custom for windows which doesnt show up many update-grub and reboots trying windows repair recovery thing while being there i also did bootrec.exe /FixBoot and update-grub and reboot again and finaly because it was so much fun, i installed linux all over again, while formatting and deleting everything linux related before that. Now that i think of it, Ubuntu also didn't notice Windows being there during the Setup and it still doesnt according to the Boot Info from Boot Repair. Boot Info Script 0.61-git-patched [23 April 2012] ============================= Boot Info Summary: =============================== => No boot loader is installed in the MBR of /dev/sda. sda1: __________________________________________________________________________ File system: vfat Boot sector type: Windows 7: FAT32 Boot sector info: No errors found in the Boot Parameter Block. Operating System: Boot files: /efi/Boot/bootx64.efi /efi/ubuntu/grubx64.efi sda2: __________________________________________________________________________ File system: Boot sector type: - Boot sector info: Mounting failed: mount: unknown filesystem type '' sda3: __________________________________________________________________________ File system: ntfs Boot sector type: Windows Vista/7: NTFS Boot sector info: No errors found in the Boot Parameter Block. Operating System: Windows 7 Boot files: /Windows/System32/winload.exe sda4: __________________________________________________________________________ File system: ext4 Boot sector type: - Boot sector info: Operating System: Ubuntu precise (development branch) Boot files: /boot/grub/grub.cfg /etc/fstab sda5: __________________________________________________________________________ File system: ext4 Boot sector type: - Boot sector info: Operating System: Boot files: sda6: __________________________________________________________________________ File system: swap Boot sector type: - Boot sector info: ============================ Drive/Partition Info: ============================= Drive: sda _____________________________________________________________________ Disk /dev/sda: 320.1 GB, 320072933376 bytes 255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes Partition Boot Start Sector End Sector # of Sectors Id System /dev/sda1 1 625,142,447 625,142,447 ee GPT GUID Partition Table detected. Partition Start Sector End Sector # of Sectors System /dev/sda1 2,048 206,847 204,800 EFI System partition /dev/sda2 206,848 468,991 262,144 Microsoft Reserved Partition (Windows) /dev/sda3 468,992 170,338,303 169,869,312 Data partition (Windows/Linux) /dev/sda4 170,338,304 330,338,304 160,000,001 Data partition (Windows/Linux) /dev/sda5 330,338,305 617,141,039 286,802,735 Data partition (Windows/Linux) /dev/sda6 617,141,040 625,141,040 8,000,001 Swap partition (Linux) "blkid" output: ________________________________________________________________ Device UUID TYPE LABEL /dev/sda1 885C-ED1B vfat /dev/sda3 EE06CC0506CBCCB1 ntfs /dev/sda4 604dd3b2-64ca-4200-b8fb-820e8d0ca899 ext4 /dev/sda5 d62515fd-8120-4a74-b17b-0bdf244124a3 ext4 /dev/sda6 7078b649-fb2a-4c59-bd03-fd31ef440d37 swap ================================ Mount points: ================================= Device Mount_Point Type Options /dev/sda1 /boot/efi vfat (rw) /dev/sda4 / ext4 (rw,errors=remount-ro) /dev/sda5 /home ext4 (rw) =========================== sda4/boot/grub/grub.cfg: =========================== -------------------------------------------------------------------------------- # # DO NOT EDIT THIS FILE # # It is automatically generated by grub-mkconfig using templates # from /etc/grub.d and settings from /etc/default/grub # ### BEGIN /etc/grub.d/00_header ### if [ -s $prefix/grubenv ]; then set have_grubenv=true load_env fi set default="0" if [ "${prev_saved_entry}" ]; then set saved_entry="${prev_saved_entry}" save_env saved_entry set prev_saved_entry= save_env prev_saved_entry set boot_once=true fi function savedefault { if [ -z "${boot_once}" ]; then saved_entry="${chosen}" save_env saved_entry fi } function recordfail { set recordfail=1 if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi } function load_video { insmod efi_gop insmod efi_uga insmod video_bochs insmod video_cirrus } insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 if loadfont /usr/share/grub/unicode.pf2 ; then set gfxmode=auto load_video insmod gfxterm insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 set locale_dir=($root)/boot/grub/locale set lang=en_US insmod gettext fi terminal_output gfxterm if [ "${recordfail}" = 1 ]; then set timeout=-1 else set timeout=10 fi ### END /etc/grub.d/00_header ### ### BEGIN /etc/grub.d/05_debian_theme ### set menu_color_normal=white/black set menu_color_highlight=black/light-gray if background_color 44,0,30; then clear fi ### END /etc/grub.d/05_debian_theme ### ### BEGIN /etc/grub.d/10_linux ### function gfxmode { set gfxpayload="$1" if [ "$1" = "keep" ]; then set vt_handoff=vt.handoff=7 else set vt_handoff= fi } if [ ${recordfail} != 1 ]; then if [ -e ${prefix}/gfxblacklist.txt ]; then if hwmatch ${prefix}/gfxblacklist.txt 3; then if [ ${match} = 0 ]; then set linux_gfx_mode=keep else set linux_gfx_mode=text fi else set linux_gfx_mode=text fi else set linux_gfx_mode=keep fi else set linux_gfx_mode=text fi export linux_gfx_mode if [ "$linux_gfx_mode" != "text" ]; then load_video; fi menuentry 'Ubuntu, with Linux 3.2.0-20-generic' --class ubuntu --class gnu-linux --class gnu --class os { recordfail gfxmode $linux_gfx_mode insmod gzio insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 linux /boot/vmlinuz-3.2.0-20-generic root=UUID=604dd3b2-64ca-4200-b8fb-820e8d0ca899 ro quiet splash $vt_handoff initrd /boot/initrd.img-3.2.0-20-generic } menuentry 'Ubuntu, with Linux 3.2.0-20-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os { recordfail insmod gzio insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 echo 'Loading Linux 3.2.0-20-generic ...' linux /boot/vmlinuz-3.2.0-20-generic root=UUID=604dd3b2-64ca-4200-b8fb-820e8d0ca899 ro recovery nomodeset echo 'Loading initial ramdisk ...' initrd /boot/initrd.img-3.2.0-20-generic } ### END /etc/grub.d/10_linux ### ### BEGIN /etc/grub.d/20_linux_xen ### ### END /etc/grub.d/20_linux_xen ### ### BEGIN /etc/grub.d/20_memtest86+ ### menuentry "Memory test (memtest86+)" { insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 linux16 /boot/memtest86+.bin } menuentry "Memory test (memtest86+, serial console 115200)" { insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 linux16 /boot/memtest86+.bin console=ttyS0,115200n8 } ### END /etc/grub.d/20_memtest86+ ### ### BEGIN /etc/grub.d/30_os-prober ### ### END /etc/grub.d/30_os-prober ### ### BEGIN /etc/grub.d/40_custom ### # This file provides an easy way to add custom menu entries. Simply type the # menu entries you want to add after this comment. Be careful not to change # the 'exec tail' line above. ### END /etc/grub.d/40_custom ### ### BEGIN /etc/grub.d/41_custom ### if [ -f $prefix/custom.cfg ]; then source $prefix/custom.cfg; fi ### END /etc/grub.d/41_custom ### -------------------------------------------------------------------------------- =============================== sda4/etc/fstab: ================================ -------------------------------------------------------------------------------- # /etc/fstab: static file system information. # # Use 'blkid' to print the universally unique identifier for a # device; this may be used with UUID= as a more robust way to name devices # that works even if disks are added and removed. See fstab(5). # # <file system> <mount point> <type> <options> <dump> <pass> proc /proc proc nodev,noexec,nosuid 0 0 # / was on /dev/sda4 during installation UUID=604dd3b2-64ca-4200-b8fb-820e8d0ca899 / ext4 errors=remount-ro 0 1 # /boot/efi was on /dev/sda1 during installation UUID=885C-ED1B /boot/efi vfat defaults 0 1 # /home was on /dev/sda5 during installation UUID=d62515fd-8120-4a74-b17b-0bdf244124a3 /home ext4 defaults 0 2 # swap was on /dev/sda6 during installation UUID=7078b649-fb2a-4c59-bd03-fd31ef440d37 none swap sw 0 0 -------------------------------------------------------------------------------- =================== sda4: Location of files loaded by Grub: ==================== GiB - GB File Fragment(s) 129.422874451 = 138.966753280 boot/grub/grub.cfg 1 83.059570312 = 89.184534528 boot/initrd.img-3.2.0-20-generic 2 101.393131256 = 108.870045696 boot/vmlinuz-3.2.0-20-generic 1 83.059570312 = 89.184534528 initrd.img 2 101.393131256 = 108.870045696 vmlinuz 1 ADDITIONAL INFORMATION : =================== log of boot-repair 2012-04-25__23h40 =================== boot-repair version : 3.18-0ppa3~precise boot-sav version : 3.18-0ppa4~precise glade2script version : 0.3.2.1-0ppa7~precise internet: connected python-software-properties version : 0.82.7 0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 591 not upgraded. dpkg-preconfigure: unable to re-open stdin: No such file or directory boot-repair is executed in installed-session (Ubuntu precise (development branch) , precise , Ubuntu , x86_64) WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted. =================== OSPROBER: /dev/sda4:The OS now in use - Ubuntu precise (development branch) CurrentSession:linux =================== BLKID: /dev/sda3: UUID="EE06CC0506CBCCB1" TYPE="ntfs" /dev/sda1: UUID="885C-ED1B" TYPE="vfat" /dev/sda4: UUID="604dd3b2-64ca-4200-b8fb-820e8d0ca899" TYPE="ext4" /dev/sda5: UUID="d62515fd-8120-4a74-b17b-0bdf244124a3" TYPE="ext4" /dev/sda6: UUID="7078b649-fb2a-4c59-bd03-fd31ef440d37" TYPE="swap" 1 disks with OS, 1 OS : 1 Linux, 0 MacOS, 0 Windows, 0 unknown type OS. WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util sfdisk doesn't support GPT. Use GNU Parted. =================== /etc/default/grub : # If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 #GRUB_HIDDEN_TIMEOUT=0 #GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" GRUB_CMDLINE_LINUX="" # Uncomment to enable BadRAM filtering, modify to suit your needs # This works with Linux (no patch required) and with any kernel that obtains # the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...) #GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef" # Uncomment to disable graphical terminal (grub-pc only) #GRUB_TERMINAL=console # The resolution used on graphical terminal # note that you can use only modes which your graphic card supports via VBE # you can see them in real GRUB with the command `vbeinfo' #GRUB_GFXMODE=640x480 # Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux #GRUB_DISABLE_LINUX_UUID=true # Uncomment to disable generation of recovery mode menu entries #GRUB_DISABLE_RECOVERY="true" # Uncomment to get a beep at grub start #GRUB_INIT_TUNE="480 440 1" EFI_OF_PART[1] (, ) =================== dmesg | grep EFI : [ 0.000000] EFI v2.00 by Lenovo [ 0.000000] Kernel-defined memdesc doesn't match the one from EFI! [ 0.000000] EFI: mem00: type=3, attr=0xf, range=[0x0000000000000000-0x0000000000001000) (0MB) [ 0.000000] EFI: mem01: type=7, attr=0xf, range=[0x0000000000001000-0x000000000004e000) (0MB) [ 0.000000] EFI: mem02: type=3, attr=0xf, range=[0x000000000004e000-0x0000000000058000) (0MB) [ 0.000000] EFI: mem03: type=10, attr=0xf, range=[0x0000000000058000-0x0000000000059000) (0MB) [ 0.000000] EFI: mem04: type=7, attr=0xf, range=[0x0000000000059000-0x000000000005e000) (0MB) [ 0.000000] EFI: mem05: type=4, attr=0xf, range=[0x000000000005e000-0x000000000005f000) (0MB) [ 0.000000] EFI: mem06: type=3, attr=0xf, range=[0x000000000005f000-0x00000000000a0000) (0MB) [ 0.000000] EFI: mem07: type=2, attr=0xf, range=[0x0000000000100000-0x00000000005b9000) (4MB) [ 0.000000] EFI: mem08: type=7, attr=0xf, range=[0x00000000005b9000-0x0000000020000000) (506MB) [ 0.000000] EFI: mem09: type=0, attr=0xf, range=[0x0000000020000000-0x0000000020200000) (2MB) [ 0.000000] EFI: mem10: type=7, attr=0xf, range=[0x0000000020200000-0x00000000364e4000) (354MB) [ 0.000000] EFI: mem11: type=2, attr=0xf, range=[0x00000000364e4000-0x000000003726a000) (13MB) [ 0.000000] EFI: mem12: type=7, attr=0xf, range=[0x000000003726a000-0x0000000040000000) (141MB) [ 0.000000] EFI: mem13: type=0, attr=0xf, range=[0x0000000040000000-0x0000000040200000) (2MB) [ 0.000000] EFI: mem14: type=7, attr=0xf, range=[0x0000000040200000-0x000000009df35000) (1501MB) [ 0.000000] EFI: mem15: type=2, attr=0xf, range=[0x000000009df35000-0x00000000d39a0000) (858MB) [ 0.000000] EFI: mem16: type=4, attr=0xf, range=[0x00000000d39a0000-0x00000000d39c0000) (0MB) [ 0.000000] EFI: mem17: type=7, attr=0xf, range=[0x00000000d39c0000-0x00000000d5df5000) (36MB) [ 0.000000] EFI: mem18: type=4, attr=0xf, range=[0x00000000d5df5000-0x00000000d6990000) (11MB) [ 0.000000] EFI: mem19: type=7, attr=0xf, range=[0x00000000d6990000-0x00000000d6b82000) (1MB) [ 0.000000] EFI: mem20: type=1, attr=0xf, range=[0x00000000d6b82000-0x00000000d6b9f000) (0MB) [ 0.000000] EFI: mem21: type=7, attr=0xf, range=[0x00000000d6b9f000-0x00000000d77b0000) (12MB) [ 0.000000] EFI: mem22: type=4, attr=0xf, range=[0x00000000d77b0000-0x00000000d780a000) (0MB) [ 0.000000] EFI: mem23: type=7, attr=0xf, range=[0x00000000d780a000-0x00000000d7826000) (0MB) [ 0.000000] EFI: mem24: type=4, attr=0xf, range=[0x00000000d7826000-0x00000000d7868000) (0MB) [ 0.000000] EFI: mem25: type=7, attr=0xf, range=[0x00000000d7868000-0x00000000d7869000) (0MB) [ 0.000000] EFI: mem26: type=4, attr=0xf, range=[0x00000000d7869000-0x00000000d786a000) (0MB) [ 0.000000] EFI: mem27: type=7, attr=0xf, range=[0x00000000d786a000-0x00000000d786b000) (0MB) [ 0.000000] EFI: mem28: type=4, attr=0xf, range=[0x00000000d786b000-0x00000000d786c000) (0MB) [ 0.000000] EFI: mem29: type=7, attr=0xf, range=[0x00000000d786c000-0x00000000d786d000) (0MB) [ 0.000000] EFI: mem30: type=4, attr=0xf, range=[0x00000000d786d000-0x00000000d825f000) (9MB) [ 0.000000] EFI: mem31: type=7, attr=0xf, range=[0x00000000d825f000-0x00000000d8261000) (0MB) [ 0.000000] EFI: mem32: type=4, attr=0xf, range=[0x00000000d8261000-0x00000000d82f7000) (0MB) [ 0.000000] EFI: mem33: type=7, attr=0xf, range=[0x00000000d82f7000-0x00000000d82f8000) (0MB) [ 0.000000] EFI: mem34: type=4, attr=0xf, range=[0x00000000d82f8000-0x00000000d8705000) (4MB) [ 0.000000] EFI: mem35: type=7, attr=0xf, range=[0x00000000d8705000-0x00000000d8706000) (0MB) [ 0.000000] EFI: mem36: type=4, attr=0xf, range=[0x00000000d8706000-0x00000000d8761000) (0MB) [ 0.000000] EFI: mem37: type=7, attr=0xf, range=[0x00000000d8761000-0x00000000d8768000) (0MB) [ 0.000000] EFI: mem38: type=4, attr=0xf, range=[0x00000000d8768000-0x00000000d9b9f000) (20MB) [ 0.000000] EFI: mem39: type=7, attr=0xf, range=[0x00000000d9b9f000-0x00000000d9e4c000) (2MB) [ 0.000000] EFI: mem40: type=2, attr=0xf, range=[0x00000000d9e4c000-0x00000000d9e52000) (0MB) [ 0.000000] EFI: mem41: type=3, attr=0xf, range=[0x00000000d9e52000-0x00000000da59f000) (7MB) [ 0.000000] EFI: mem42: type=5, attr=0x800000000000000f, range=[0x00000000da59f000-0x00000000da6c3000) (1MB) [ 0.000000] EFI: mem43: type=5, attr=0x800000000000000f, range=[0x00000000da6c3000-0x00000000da79f000) (0MB) [ 0.000000] EFI: mem44: type=6, attr=0x800000000000000f, range=[0x00000000da79f000-0x00000000da8b1000) (1MB) [ 0.000000] EFI: mem45: type=6, attr=0x800000000000000f, range=[0x00000000da8b1000-0x00000000da99f000) (0MB) [ 0.000000] EFI: mem46: type=0, attr=0xf, range=[0x00000000da99f000-0x00000000daa22000) (0MB) [ 0.000000] EFI: mem47: type=0, attr=0xf, range=[0x00000000daa22000-0x00000000daa9b000) (0MB) [ 0.000000] EFI: mem48: type=0, attr=0xf, range=[0x00000000daa9b000-0x00000000daa9c000) (0MB) [ 0.000000] EFI: mem49: type=0, attr=0xf, range=[0x00000000daa9c000-0x00000000daa9f000) (0MB) [ 0.000000] EFI: mem50: type=10, attr=0xf, range=[0x00000000daa9f000-0x00000000daadd000) (0MB) [ 0.000000] EFI: mem51: type=10, attr=0xf, range=[0x00000000daadd000-0x00000000dab9f000) (0MB) [ 0.000000] EFI: mem52: type=9, attr=0xf, range=[0x00000000dab9f000-0x00000000dabdc000) (0MB) [ 0.000000] EFI: mem53: type=9, attr=0xf, range=[0x00000000dabdc000-0x00000000dabff000) (0MB) [ 0.000000] EFI: mem54: type=4, attr=0xf, range=[0x00000000dabff000-0x00000000dac00000) (0MB) [ 0.000000] EFI: mem55: type=7, attr=0xf, range=[0x0000000100000000-0x000000021e600000) (4582MB) [ 0.000000] EFI: mem56: type=11, attr=0x8000000000000001, range=[0x00000000f80f8000-0x00000000f80f9000) (0MB) [ 0.000000] EFI: mem57: type=11, attr=0x8000000000000001, range=[0x00000000fed1c000-0x00000000fed20000) (0MB) [ 0.000000] ACPI: UEFI 00000000dabde000 0003E (v01 LENOVO TP-8D 00001280 PTL 00000002) [ 0.000000] ACPI: UEFI 00000000dabdd000 00042 (v01 PTL COMBUF 00000001 PTL 00000001) [ 0.000000] ACPI: UEFI 00000000dabdc000 00292 (v01 LENOVO TP-8D 00001280 PTL 00000002) [ 0.795807] fb0: EFI VGA frame buffer device [ 1.057243] EFI Variables Facility v0.08 2004-May-17 [ 9.122104] fb: conflicting fb hw usage inteldrmfb vs EFI VGA - removing generic driver ReadEFI: /dev/sda , N 128 , 0 , , PRStart 1024 , PRSize 128 WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted. =================== PARTITIONS & DISKS: sda4 : sda, not-sepboot, grubenv-ok grub2, grub-efi, update-grub, 64, with-boot, is-os, gpt-but-not-EFI, fstab-has-bad-efi, no-nt, no-winload, no-recov-nor-hid, no-bmgr, no-grldr, no-b-bcd, apt-get, grub-install, . sda3 : sda, maybesepboot, no-grubenv nogrub, no-docgrub, no-update-grub, 32, no-boot, no-os, gpt-but-not-EFI, part-has-no-fstab, no-nt, haswinload, no-recov-nor-hid, no-bmgr, no-grldr, no-b-bcd, nopakmgr, nogrubinstall, /mnt/boot-sav/sda3. sda1 : sda, maybesepboot, no-grubenv nogrub, no-docgrub, no-update-grub, 32, no-boot, no-os, is-correct-EFI, part-has-no-fstab, no-nt, no-winload, no-recov-nor-hid, no-bmgr, no-grldr, no-b-bcd, nopakmgr, nogrubinstall, /boot/efi. sda5 : sda, maybesepboot, no-grubenv nogrub, no-docgrub, no-update-grub, 32, no-boot, no-os, gpt-but-not-EFI, part-has-no-fstab, no-nt, no-winload, no-recov-nor-hid, no-bmgr, no-grldr, no-b-bcd, nopakmgr, nogrubinstall, /home. sda : GPT-BIS, GPT, no-BIOS_boot, has-correctEFI, 2048 sectors * 512 bytes =================== PARTED: Model: ATA HITACHI HTS72323 (scsi) Disk /dev/sda: 320GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 1049kB 106MB 105MB fat32 EFI system partition boot 2 106MB 240MB 134MB Microsoft reserved partition msftres 3 240MB 87.2GB 87.0GB ntfs Basic data partition 4 87.2GB 169GB 81.9GB ext4 5 169GB 316GB 147GB ext4 6 316GB 320GB 4096MB linux-swap(v1) =================== MOUNT: /dev/sda4 on / type ext4 (rw,errors=remount-ro) proc on /proc type proc (rw,noexec,nosuid,nodev) sysfs on /sys type sysfs (rw,noexec,nosuid,nodev) none on /sys/fs/fuse/connections type fusectl (rw) none on /sys/kernel/debug type debugfs (rw) none on /sys/kernel/security type securityfs (rw) udev on /dev type devtmpfs (rw,mode=0755) devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620) tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755) none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880) none on /run/shm type tmpfs (rw,nosuid,nodev) /dev/sda1 on /boot/efi type vfat (rw) /dev/sda5 on /home type ext4 (rw) gvfs-fuse-daemon on /home/vierlex/.gvfs type fuse.gvfs-fuse-daemon (rw,nosuid,nodev,user=vierlex) /dev/sda3 on /mnt/boot-sav/sda3 type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096) /sys/block/sda: alignment_offset bdi capability dev device discard_alignment events events_async events_poll_msecs ext_range holders inflight power queue range removable ro sda1 sda2 sda3 sda4 sda5 sda6 size slaves stat subsystem trace uevent /dev: agpgart autofs block bsg btrfs-control bus char console core cpu cpu_dma_latency disk dri ecryptfs fb0 fd full fuse hpet input kmsg log mapper mcelog mei mem net network_latency network_throughput null oldmem port ppp psaux ptmx pts random rfkill rtc rtc0 sda sda1 sda2 sda3 sda4 sda5 sda6 sg0 shm snapshot snd stderr stdin stdout tpm0 uinput urandom usbmon0 usbmon1 usbmon2 v4l vga_arbiter video0 watchdog zero /dev/mapper: control /boot/efi: EFI /boot/efi/EFI: Boot Microsoft ubuntu /boot/efi/efi: Boot Microsoft ubuntu /boot/efi/efi/Boot: bootx64.efi /boot/efi/efi/ubuntu: grubx64.efi WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted. =================== DF: Filesystem Type Size Used Avail Use% Mounted on /dev/sda4 ext4 77G 4.1G 69G 6% / udev devtmpfs 3.9G 12K 3.9G 1% /dev tmpfs tmpfs 1.6G 864K 1.6G 1% /run none tmpfs 5.0M 0 5.0M 0% /run/lock none tmpfs 3.9G 152K 3.9G 1% /run/shm /dev/sda1 vfat 96M 18M 79M 19% /boot/efi /dev/sda5 ext4 137G 2.2G 128G 2% /home /dev/sda3 fuseblk 81G 30G 52G 37% /mnt/boot-sav/sda3 =================== FDISK: Disk /dev/sda: 320.1 GB, 320072933376 bytes 255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xf34fe538 Device Boot Start End Blocks Id System /dev/sda1 1 625142447 312571223+ ee GPT =================== Before mainwindow FSCK no PASTEBIN yes WUBI no WINBOOT yes recommendedrepair, purge, QTY_OF_PART_FOR_REINSTAL 1 no-kernel-purge UNHIDEBOOT_ACTION yes (10s), noflag () PART_TO_REINSTALL_GRUB sda4, FORCE_GRUB no (sda) REMOVABLEDISK no USE_SEPARATEBOOTPART no (sda3) grub2 () UNCOMMENT_GFXMODE no ATA ADD_KERNEL_OPTION no (acpi=off) MBR_TO_RESTORE ( ) EFI detected. Please check the options. =================== Actions FSCK no PASTEBIN yes WUBI no WINBOOT no bootinfo, nombraction, QTY_OF_PART_FOR_REINSTAL 1 no-kernel-purge UNHIDEBOOT_ACTION no (10s), noflag () PART_TO_REINSTALL_GRUB sda4, FORCE_GRUB no (sda) REMOVABLEDISK no USE_SEPARATEBOOTPART no (sda3) grub2 () UNCOMMENT_GFXMODE no ATA ADD_KERNEL_OPTION no (acpi=off) MBR_TO_RESTORE ( ) No change has been performed on your computer. See you soon! internet: connected Thanks for your time and attention. EDIT: additional Info Request =No boot loader is installed in the MBR of /dev/sda. But maybe this is how it is supposed to work? yea this is ok. boot stuff seems to be on a seperate partition, in my case sda1. I'm very new to this UEFI thing too. missing files like bootmgr i don't really have a clue :D but yea, maybe thats how it suppose to be? Instead and whats not shown in the log for some reason: There is additional microsoft bootfiles on sda1 under /efi/microsoft/ [much stuff] I remember also doing some kind of hack to make a UEFI windows 7 usb stick. http://jake.io/b/2011/installing-windows-7-with-uefi-boot-on-an-x220-from-usb/ In short: creating and placing bootx64.efi on the stick so it can be booted in UEFI mode. boot order i decide that in my BIOS. i read somwhere that the thinkpad x220 (essential part of the serial number: 4921 http://www.lenovo.com/shop/americas/content/user_guides/x220_x220i_x220tablet_x220itablet_ug_en.pdf) doesnt really have UEFI interface or something, still, these 2 options are listed with all the other usual devices you can give a boot priority to. Right now it looks like this: Boot Priority Order 1. ubuntu 2. Windows Boot Manager 3. USB FDD 4. USB HDD 5. ATA HDD0 HITACHI [random string]

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New features of C# 4.0

This article covers New features of C# 4.0. Article has been divided into below sections. Introduction. Dynamic Lookup. Named and Optional Arguments. Features for COM interop. Variance. Relationship with Visual Basic. Resources. Other interested readings… 22 New Features of Visual Studio 2008 for .NET Professionals 50 New Features of SQL Server 2008 IIS 7.0 New features Introduction It is now close to a year since Microsoft Visual C# 3.0 shipped as part of Visual Studio 2008. In the VS Managed Languages team we are hard at work on creating the next version of the language (with the unsurprising working title of C# 4.0), and this document is a first public description of the planned language features as we currently see them. Please be advised that all this is in early stages of production and is subject to change. Part of the reason for sharing our plans in public so early is precisely to get the kind of feedback that will cause us to improve the final product before it rolls out. Simultaneously with the publication of this whitepaper, a first public CTP (community technology preview) of Visual Studio 2010 is going out as a Virtual PC image for everyone to try. Please use it to play and experiment with the features, and let us know of any thoughts you have. We ask for your understanding and patience working with very early bits, where especially new or newly implemented features do not have the quality or stability of a final product. The aim of the CTP is not to give you a productive work environment but to give you the best possible impression of what we are working on for the next release. The CTP contains a number of walkthroughs, some of which highlight the new language features of C# 4.0. Those are excellent for getting a hands-on guided tour through the details of some common scenarios for the features. You may consider this whitepaper a companion document to these walkthroughs, complementing them with a focus on the overall language features and how they work, as opposed to the specifics of the concrete scenarios. C# 4.0 The major theme for C# 4.0 is dynamic programming. Increasingly, objects are “dynamic” in the sense that their structure and behavior is not captured by a static type, or at least not one that the compiler knows about when compiling your program. Some examples include a. objects from dynamic programming languages, such as Python or Ruby b. COM objects accessed through IDispatch c. ordinary .NET types accessed through reflection d. objects with changing structure, such as HTML DOM objects While C# remains a statically typed language, we aim to vastly improve the interaction with such objects. A secondary theme is co-evolution with Visual Basic. Going forward we will aim to maintain the individual character of each language, but at the same time important new features should be introduced in both languages at the same time. They should be differentiated more by style and feel than by feature set. The new features in C# 4.0 fall into four groups: Dynamic lookup Dynamic lookup allows you to write method, operator and indexer calls, property and field accesses, and even object invocations which bypass the C# static type checking and instead gets resolved at runtime. Named and optional parameters Parameters in C# can now be specified as optional by providing a default value for them in a member declaration. When the member is invoked, optional arguments can be omitted. Furthermore, any argument can be passed by parameter name instead of position. COM specific interop features Dynamic lookup as well as named and optional parameters both help making programming against COM less painful than today. On top of that, however, we are adding a number of other small features that further improve the interop experience. Variance It used to be that an IEnumerable<string> wasn’t an IEnumerable<object>. Now it is – C# embraces type safe “co-and contravariance” and common BCL types are updated to take advantage of that. Dynamic Lookup Dynamic lookup allows you a unified approach to invoking things dynamically. With dynamic lookup, when you have an object in your hand you do not need to worry about whether it comes from COM, IronPython, the HTML DOM or reflection; you just apply operations to it and leave it to the runtime to figure out what exactly those operations mean for that particular object. This affords you enormous flexibility, and can greatly simplify your code, but it does come with a significant drawback: Static typing is not maintained for these operations. A dynamic object is assumed at compile time to support any operation, and only at runtime will you get an error if it wasn’t so. Oftentimes this will be no loss, because the object wouldn’t have a static type anyway, in other cases it is a tradeoff between brevity and safety. In order to facilitate this tradeoff, it is a design goal of C# to allow you to opt in or opt out of dynamic behavior on every single call. The dynamic type C# 4.0 introduces a new static type called dynamic. When you have an object of type dynamic you can “do things to it” that are resolved only at runtime: dynamic d = GetDynamicObject(…); d.M(7); The C# compiler allows you to call a method with any name and any arguments on d because it is of type dynamic. At runtime the actual object that d refers to will be examined to determine what it means to “call M with an int” on it. The type dynamic can be thought of as a special version of the type object, which signals that the object can be used dynamically. It is easy to opt in or out of dynamic behavior: any object can be implicitly converted to dynamic, “suspending belief” until runtime. Conversely, there is an “assignment conversion” from dynamic to any other type, which allows implicit conversion in assignment-like constructs: dynamic d = 7; // implicit conversion int i = d; // assignment conversion Dynamic operations Not only method calls, but also field and property accesses, indexer and operator calls and even delegate invocations can be dispatched dynamically: dynamic d = GetDynamicObject(…); d.M(7); // calling methods d.f = d.P; // getting and settings fields and properties d[“one”] = d[“two”]; // getting and setting thorugh indexers int i = d + 3; // calling operators string s = d(5,7); // invoking as a delegate The role of the C# compiler here is simply to package up the necessary information about “what is being done to d”, so that the runtime can pick it up and determine what the exact meaning of it is given an actual object d. Think of it as deferring part of the compiler’s job to runtime. The result of any dynamic operation is itself of type dynamic. Runtime lookup At runtime a dynamic operation is dispatched according to the nature of its target object d: COM objects If d is a COM object, the operation is dispatched dynamically through COM IDispatch. This allows calling to COM types that don’t have a Primary Interop Assembly (PIA), and relying on COM features that don’t have a counterpart in C#, such as indexed properties and default properties. Dynamic objects If d implements the interface IDynamicObject d itself is asked to perform the operation. Thus by implementing IDynamicObject a type can completely redefine the meaning of dynamic operations. This is used intensively by dynamic languages such as IronPython and IronRuby to implement their own dynamic object models. It will also be used by APIs, e.g. by the HTML DOM to allow direct access to the object’s properties using property syntax. Plain objects Otherwise d is a standard .NET object, and the operation will be dispatched using reflection on its type and a C# “runtime binder” which implements C#’s lookup and overload resolution semantics at runtime. This is essentially a part of the C# compiler running as a runtime component to “finish the work” on dynamic operations that was deferred by the static compiler. Example Assume the following code: dynamic d1 = new Foo(); dynamic d2 = new Bar(); string s; d1.M(s, d2, 3, null); Because the receiver of the call to M is dynamic, the C# compiler does not try to resolve the meaning of the call. Instead it stashes away information for the runtime about the call. This information (often referred to as the “payload”) is essentially equivalent to: “Perform an instance method call of M with the following arguments: 1. a string 2. a dynamic 3. a literal int 3 4. a literal object null” At runtime, assume that the actual type Foo of d1 is not a COM type and does not implement IDynamicObject. In this case the C# runtime binder picks up to finish the overload resolution job based on runtime type information, proceeding as follows: 1. Reflection is used to obtain the actual runtime types of the two objects, d1 and d2, that did not have a static type (or rather had the static type dynamic). The result is Foo for d1 and Bar for d2. 2. Method lookup and overload resolution is performed on the type Foo with the call M(string,Bar,3,null) using ordinary C# semantics. 3. If the method is found it is invoked; otherwise a runtime exception is thrown. Overload resolution with dynamic arguments Even if the receiver of a method call is of a static type, overload resolution can still happen at runtime. This can happen if one or more of the arguments have the type dynamic: Foo foo = new Foo(); dynamic d = new Bar(); var result = foo.M(d); The C# runtime binder will choose between the statically known overloads of M on Foo, based on the runtime type of d, namely Bar. The result is again of type dynamic. The Dynamic Language Runtime An important component in the underlying implementation of dynamic lookup is the Dynamic Language Runtime (DLR), which is a new API in .NET 4.0. The DLR provides most of the infrastructure behind not only C# dynamic lookup but also the implementation of several dynamic programming languages on .NET, such as IronPython and IronRuby. Through this common infrastructure a high degree of interoperability is ensured, but just as importantly the DLR provides excellent caching mechanisms which serve to greatly enhance the efficiency of runtime dispatch. To the user of dynamic lookup in C#, the DLR is invisible except for the improved efficiency. However, if you want to implement your own dynamically dispatched objects, the IDynamicObject interface allows you to interoperate with the DLR and plug in your own behavior. This is a rather advanced task, which requires you to understand a good deal more about the inner workings of the DLR. For API writers, however, it can definitely be worth the trouble in order to vastly improve the usability of e.g. a library representing an inherently dynamic domain. Open issues There are a few limitations and things that might work differently than you would expect. · The DLR allows objects to be created from objects that represent classes. However, the current implementation of C# doesn’t have syntax to support this. · Dynamic lookup will not be able to find extension methods. Whether extension methods apply or not depends on the static context of the call (i.e. which using clauses occur), and this context information is not currently kept as part of the payload. · Anonymous functions (i.e. lambda expressions) cannot appear as arguments to a dynamic method call. The compiler cannot bind (i.e. “understand”) an anonymous function without knowing what type it is converted to. One consequence of these limitations is that you cannot easily use LINQ queries over dynamic objects: dynamic collection = …; var result = collection.Select(e => e + 5); If the Select method is an extension method, dynamic lookup will not find it. Even if it is an instance method, the above does not compile, because a lambda expression cannot be passed as an argument to a dynamic operation. There are no plans to address these limitations in C# 4.0. Named and Optional Arguments Named and optional parameters are really two distinct features, but are often useful together. Optional parameters allow you to omit arguments to member invocations, whereas named arguments is a way to provide an argument using the name of the corresponding parameter instead of relying on its position in the parameter list. Some APIs, most notably COM interfaces such as the Office automation APIs, are written specifically with named and optional parameters in mind. Up until now it has been very painful to call into these APIs from C#, with sometimes as many as thirty arguments having to be explicitly passed, most of which have reasonable default values and could be omitted. Even in APIs for .NET however you sometimes find yourself compelled to write many overloads of a method with different combinations of parameters, in order to provide maximum usability to the callers. Optional parameters are a useful alternative for these situations. Optional parameters A parameter is declared optional simply by providing a default value for it: public void M(int x, int y = 5, int z = 7); Here y and z are optional parameters and can be omitted in calls: M(1, 2, 3); // ordinary call of M M(1, 2); // omitting z – equivalent to M(1, 2, 7) M(1); // omitting both y and z – equivalent to M(1, 5, 7) Named and optional arguments C# 4.0 does not permit you to omit arguments between commas as in M(1,,3). This could lead to highly unreadable comma-counting code. Instead any argument can be passed by name. Thus if you want to omit only y from a call of M you can write: M(1, z: 3); // passing z by name or M(x: 1, z: 3); // passing both x and z by name or even M(z: 3, x: 1); // reversing the order of arguments All forms are equivalent, except that arguments are always evaluated in the order they appear, so in the last example the 3 is evaluated before the 1. Optional and named arguments can be used not only with methods but also with indexers and constructors. Overload resolution Named and optional arguments affect overload resolution, but the changes are relatively simple: A signature is applicable if all its parameters are either optional or have exactly one corresponding argument (by name or position) in the call which is convertible to the parameter type. Betterness rules on conversions are only applied for arguments that are explicitly given – omitted optional arguments are ignored for betterness purposes. If two signatures are equally good, one that does not omit optional parameters is preferred. M(string s, int i = 1); M(object o); M(int i, string s = “Hello”); M(int i); M(5); Given these overloads, we can see the working of the rules above. M(string,int) is not applicable because 5 doesn’t convert to string. M(int,string) is applicable because its second parameter is optional, and so, obviously are M(object) and M(int). M(int,string) and M(int) are both better than M(object) because the conversion from 5 to int is better than the conversion from 5 to object. Finally M(int) is better than M(int,string) because no optional arguments are omitted. Thus the method that gets called is M(int). Features for COM interop Dynamic lookup as well as named and optional parameters greatly improve the experience of interoperating with COM APIs such as the Office Automation APIs. In order to remove even more of the speed bumps, a couple of small COM-specific features are also added to C# 4.0. Dynamic import Many COM methods accept and return variant types, which are represented in the PIAs as object. In the vast majority of cases, a programmer calling these methods already knows the static type of a returned object from context, but explicitly has to perform a cast on the returned value to make use of that knowledge. These casts are so common that they constitute a major nuisance. In order to facilitate a smoother experience, you can now choose to import these COM APIs in such a way that variants are instead represented using the type dynamic. In other words, from your point of view, COM signatures now have occurrences of dynamic instead of object in them. This means that you can easily access members directly off a returned object, or you can assign it to a strongly typed local variable without having to cast. To illustrate, you can now say excel.Cells[1, 1].Value = "Hello"; instead of ((Excel.Range)excel.Cells[1, 1]).Value2 = "Hello"; and Excel.Range range = excel.Cells[1, 1]; instead of Excel.Range range = (Excel.Range)excel.Cells[1, 1]; Compiling without PIAs Primary Interop Assemblies are large .NET assemblies generated from COM interfaces to facilitate strongly typed interoperability. They provide great support at design time, where your experience of the interop is as good as if the types where really defined in .NET. However, at runtime these large assemblies can easily bloat your program, and also cause versioning issues because they are distributed independently of your application. The no-PIA feature allows you to continue to use PIAs at design time without having them around at runtime. Instead, the C# compiler will bake the small part of the PIA that a program actually uses directly into its assembly. At runtime the PIA does not have to be loaded. Omitting ref Because of a different programming model, many COM APIs contain a lot of reference parameters. Contrary to refs in C#, these are typically not meant to mutate a passed-in argument for the subsequent benefit of the caller, but are simply another way of passing value parameters. It therefore seems unreasonable that a C# programmer should have to create temporary variables for all such ref parameters and pass these by reference. Instead, specifically for COM methods, the C# compiler will allow you to pass arguments by value to such a method, and will automatically generate temporary variables to hold the passed-in values, subsequently discarding these when the call returns. In this way the caller sees value semantics, and will not experience any side effects, but the called method still gets a reference. Open issues A few COM interface features still are not surfaced in C#. Most notably these include indexed properties and default properties. As mentioned above these will be respected if you access COM dynamically, but statically typed C# code will still not recognize them. There are currently no plans to address these remaining speed bumps in C# 4.0. Variance An aspect of generics that often comes across as surprising is that the following is illegal: IList<string> strings = new List<string>(); IList<object> objects = strings; The second assignment is disallowed because strings does not have the same element type as objects. There is a perfectly good reason for this. If it were allowed you could write: objects[0] = 5; string s = strings[0]; Allowing an int to be inserted into a list of strings and subsequently extracted as a string. This would be a breach of type safety. However, there are certain interfaces where the above cannot occur, notably where there is no way to insert an object into the collection. Such an interface is IEnumerable<T>. If instead you say: IEnumerable<object> objects = strings; There is no way we can put the wrong kind of thing into strings through objects, because objects doesn’t have a method that takes an element in. Variance is about allowing assignments such as this in cases where it is safe. The result is that a lot of situations that were previously surprising now just work. Covariance In .NET 4.0 the IEnumerable<T> interface will be declared in the following way: public interface IEnumerable<out T> : IEnumerable { IEnumerator<T> GetEnumerator(); } public interface IEnumerator<out T> : IEnumerator { bool MoveNext(); T Current { get; } } The “out” in these declarations signifies that the T can only occur in output position in the interface – the compiler will complain otherwise. In return for this restriction, the interface becomes “covariant” in T, which means that an IEnumerable<A> is considered an IEnumerable<B> if A has a reference conversion to B. As a result, any sequence of strings is also e.g. a sequence of objects. This is useful e.g. in many LINQ methods. Using the declarations above: var result = strings.Union(objects); // succeeds with an IEnumerable<object> This would previously have been disallowed, and you would have had to to some cumbersome wrapping to get the two sequences to have the same element type. Contravariance Type parameters can also have an “in” modifier, restricting them to occur only in input positions. An example is IComparer<T>: public interface IComparer<in T> { public int Compare(T left, T right); } The somewhat baffling result is that an IComparer<object> can in fact be considered an IComparer<string>! It makes sense when you think about it: If a comparer can compare any two objects, it can certainly also compare two strings. This property is referred to as contravariance. A generic type can have both in and out modifiers on its type parameters, as is the case with the Func<…> delegate types: public delegate TResult Func<in TArg, out TResult>(TArg arg); Obviously the argument only ever comes in, and the result only ever comes out. Therefore a Func<object,string> can in fact be used as a Func<string,object>. Limitations Variant type parameters can only be declared on interfaces and delegate types, due to a restriction in the CLR. Variance only applies when there is a reference conversion between the type arguments. For instance, an IEnumerable<int> is not an IEnumerable<object> because the conversion from int to object is a boxing conversion, not a reference conversion. Also please note that the CTP does not contain the new versions of the .NET types mentioned above. In order to experiment with variance you have to declare your own variant interfaces and delegate types. COM Example Here is a larger Office automation example that shows many of the new C# features in action. using System; using System.Diagnostics; using System.Linq; using Excel = Microsoft.Office.Interop.Excel; using Word = Microsoft.Office.Interop.Word; class Program { static void Main(string[] args) { var excel = new Excel.Application(); excel.Visible = true; excel.Workbooks.Add(); // optional arguments omitted excel.Cells[1, 1].Value = "Process Name"; // no casts; Value dynamically excel.Cells[1, 2].Value = "Memory Usage"; // accessed var processes = Process.GetProcesses() .OrderByDescending(p => p.WorkingSet) .Take(10); int i = 2; foreach (var p in processes) { excel.Cells[i, 1].Value = p.ProcessName; // no casts excel.Cells[i, 2].Value = p.WorkingSet; // no casts i++; } Excel.Range range = excel.Cells[1, 1]; // no casts Excel.Chart chart = excel.ActiveWorkbook.Charts. Add(After: excel.ActiveSheet); // named and optional arguments chart.ChartWizard( Source: range.CurrentRegion, Title: "Memory Usage in " + Environment.MachineName); //named+optional chart.ChartStyle = 45; chart.CopyPicture(Excel.XlPictureAppearance.xlScreen, Excel.XlCopyPictureFormat.xlBitmap, Excel.XlPictureAppearance.xlScreen); var word = new Word.Application(); word.Visible = true; word.Documents.Add(); // optional arguments word.Selection.Paste(); } } The code is much more terse and readable than the C# 3.0 counterpart. Note especially how the Value property is accessed dynamically. This is actually an indexed property, i.e. a property that takes an argument; something which C# does not understand. However the argument is optional. Since the access is dynamic, it goes through the runtime COM binder which knows to substitute the default value and call the indexed property. Thus, dynamic COM allows you to avoid accesses to the puzzling Value2 property of Excel ranges. Relationship with Visual Basic A number of the features introduced to C# 4.0 already exist or will be introduced in some form or other in Visual Basic: · Late binding in VB is similar in many ways to dynamic lookup in C#, and can be expected to make more use of the DLR in the future, leading to further parity with C#. · Named and optional arguments have been part of Visual Basic for a long time, and the C# version of the feature is explicitly engineered with maximal VB interoperability in mind. · NoPIA and variance are both being introduced to VB and C# at the same time. VB in turn is adding a number of features that have hitherto been a mainstay of C#. As a result future versions of C# and VB will have much better feature parity, for the benefit of everyone. Resources All available resources concerning C# 4.0 can be accessed through the C# Dev Center. Specifically, this white paper and other resources can be found at the Code Gallery site. Enjoy! span.fullpost {display:none;}

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Toorcon14

- by danx

Toorcon 2012 Information Security Conference San Diego, CA, http://www.toorcon.org/ Dan Anderson, October 2012 It's almost Halloween, and we all know what that means—yes, of course, it's time for another Toorcon Conference! Toorcon is an annual conference for people interested in computer security. This includes the whole range of hackers, computer hobbyists, professionals, security consultants, press, law enforcement, prosecutors, FBI, etc. We're at Toorcon 14—see earlier blogs for some of the previous Toorcon's I've attended (back to 2003). This year's "con" was held at the Westin on Broadway in downtown San Diego, California. The following are not necessarily my views—I'm just the messenger—although I could have misquoted or misparaphrased the speakers. Also, I only reviewed some of the talks, below, which I attended and interested me. MalAndroid—the Crux of Android Infections, Aditya K. Sood Programming Weird Machines with ELF Metadata, Rebecca "bx" Shapiro Privacy at the Handset: New FCC Rules?, Valkyrie Hacking Measured Boot and UEFI, Dan Griffin You Can't Buy Security: Building the Open Source InfoSec Program, Boris Sverdlik What Journalists Want: The Investigative Reporters' Perspective on Hacking, Dave Maas & Jason Leopold Accessibility and Security, Anna Shubina Stop Patching, for Stronger PCI Compliance, Adam Brand McAfee Secure & Trustmarks — a Hacker's Best Friend, Jay James & Shane MacDougall MalAndroid—the Crux of Android Infections Aditya K. Sood, IOActive, Michigan State PhD candidate Aditya talked about Android smartphone malware. There's a lot of old Android software out there—over 50% Gingerbread (2.3.x)—and most have unpatched vulnerabilities. Of 9 Android vulnerabilities, 8 have known exploits (such as the old Gingerbread Global Object Table exploit). Android protection includes sandboxing, security scanner, app permissions, and screened Android app market. The Android permission checker has fine-grain resource control, policy enforcement. Android static analysis also includes a static analysis app checker (bouncer), and a vulnerablity checker. What security problems does Android have? User-centric security, which depends on the user to grant permission and make smart decisions. But users don't care or think about malware (the're not aware, not paranoid). All they want is functionality, extensibility, mobility Android had no "proper" encryption before Android 3.0 No built-in protection against social engineering and web tricks Alternative Android app markets are unsafe. Simply visiting some markets can infect Android Aditya classified Android Malware types as: Type A—Apps. These interact with the Android app framework. For example, a fake Netflix app. Or Android Gold Dream (game), which uploads user files stealthy manner to a remote location. Type K—Kernel. Exploits underlying Linux libraries or kernel Type H—Hybrid. These use multiple layers (app framework, libraries, kernel). These are most commonly used by Android botnets, which are popular with Chinese botnet authors What are the threats from Android malware? These incude leak info (contacts), banking fraud, corporate network attacks, malware advertising, malware "Hackivism" (the promotion of social causes. For example, promiting specific leaders of the Tunisian or Iranian revolutions. Android malware is frequently "masquerated". That is, repackaged inside a legit app with malware. To avoid detection, the hidden malware is not unwrapped until runtime. The malware payload can be hidden in, for example, PNG files. Less common are Android bootkits—there's not many around. What they do is hijack the Android init framework—alteering system programs and daemons, then deletes itself. For example, the DKF Bootkit (China). Android App Problems: no code signing! all self-signed native code execution permission sandbox — all or none alternate market places no robust Android malware detection at network level delayed patch process Programming Weird Machines with ELF Metadata Rebecca "bx" Shapiro, Dartmouth College, NH https://github.com/bx/elf-bf-tools @bxsays on twitter Definitions. "ELF" is an executable file format used in linking and loading executables (on UNIX/Linux-class machines). "Weird machine" uses undocumented computation sources (I think of them as unintended virtual machines). Some examples of "weird machines" are those that: return to weird location, does SQL injection, corrupts the heap. Bx then talked about using ELF metadata as (an uintended) "weird machine". Some ELF background: A compiler takes source code and generates a ELF object file (hello.o). A static linker makes an ELF executable from the object file. A runtime linker and loader takes ELF executable and loads and relocates it in memory. The ELF file has symbols to relocate functions and variables. ELF has two relocation tables—one at link time and another one at loading time: .rela.dyn (link time) and .dynsym (dynamic table). GOT: Global Offset Table of addresses for dynamically-linked functions. PLT: Procedure Linkage Tables—works with GOT. The memory layout of a process (not the ELF file) is, in order: program (+ heap), dynamic libraries, libc, ld.so, stack (which includes the dynamic table loaded into memory) For ELF, the "weird machine" is found and exploited in the loader. ELF can be crafted for executing viruses, by tricking runtime into executing interpreted "code" in the ELF symbol table. One can inject parasitic "code" without modifying the actual ELF code portions. Think of the ELF symbol table as an "assembly language" interpreter. It has these elements: instructions: Add, move, jump if not 0 (jnz) Think of symbol table entries as "registers" symbol table value is "contents" immediate values are constants direct values are addresses (e.g., 0xdeadbeef) move instruction: is a relocation table entry add instruction: relocation table "addend" entry jnz instruction: takes multiple relocation table entries The ELF weird machine exploits the loader by relocating relocation table entries. The loader will go on forever until told to stop. It stores state on stack at "end" and uses IFUNC table entries (containing function pointer address). The ELF weird machine, called "Brainfu*k" (BF) has: 8 instructions: pointer inc, dec, inc indirect, dec indirect, jump forward, jump backward, print. Three registers - 3 registers Bx showed example BF source code that implemented a Turing machine printing "hello, world". More interesting was the next demo, where bx modified ping. Ping runs suid as root, but quickly drops privilege. BF modified the loader to disable the library function call dropping privilege, so it remained as root. Then BF modified the ping -t argument to execute the -t filename as root. It's best to show what this modified ping does with an example: $ whoami bx $ ping localhost -t backdoor.sh # executes backdoor $ whoami root $ The modified code increased from 285948 bytes to 290209 bytes. A BF tool compiles "executable" by modifying the symbol table in an existing ELF executable. The tool modifies .dynsym and .rela.dyn table, but not code or data. Privacy at the Handset: New FCC Rules? "Valkyrie" (Christie Dudley, Santa Clara Law JD candidate) Valkyrie talked about mobile handset privacy. Some background: Senator Franken (also a comedian) became alarmed about CarrierIQ, where the carriers track their customers. Franken asked the FCC to find out what obligations carriers think they have to protect privacy. The carriers' response was that they are doing just fine with self-regulation—no worries! Carriers need to collect data, such as missed calls, to maintain network quality. But carriers also sell data for marketing. Verizon sells customer data and enables this with a narrow privacy policy (only 1 month to opt out, with difficulties). The data sold is not individually identifiable and is aggregated. But Verizon recommends, as an aggregation workaround to "recollate" data to other databases to identify customers indirectly. The FCC has regulated telephone privacy since 1934 and mobile network privacy since 2007. Also, the carriers say mobile phone privacy is a FTC responsibility (not FCC). FTC is trying to improve mobile app privacy, but FTC has no authority over carrier / customer relationships. As a side note, Apple iPhones are unique as carriers have extra control over iPhones they don't have with other smartphones. As a result iPhones may be more regulated. Who are the consumer advocates? Everyone knows EFF, but EPIC (Electrnic Privacy Info Center), although more obsecure, is more relevant. What to do? Carriers must be accountable. Opt-in and opt-out at any time. Carriers need incentive to grant users control for those who want it, by holding them liable and responsible for breeches on their clock. Location information should be added current CPNI privacy protection, and require "Pen/trap" judicial order to obtain (and would still be a lower standard than 4th Amendment). Politics are on a pro-privacy swing now, with many senators and the Whitehouse. There will probably be new regulation soon, and enforcement will be a problem, but consumers will still have some benefit. Hacking Measured Boot and UEFI Dan Griffin, JWSecure, Inc., Seattle, @JWSdan Dan talked about hacking measured UEFI boot. First some terms: UEFI is a boot technology that is replacing BIOS (has whitelisting and blacklisting). UEFI protects devices against rootkits. TPM - hardware security device to store hashs and hardware-protected keys "secure boot" can control at firmware level what boot images can boot "measured boot" OS feature that tracks hashes (from BIOS, boot loader, krnel, early drivers). "remote attestation" allows remote validation and control based on policy on a remote attestation server. Microsoft pushing TPM (Windows 8 required), but Google is not. Intel TianoCore is the only open source for UEFI. Dan has Measured Boot Tool at http://mbt.codeplex.com/ with a demo where you can also view TPM data. TPM support already on enterprise-class machines. UEFI Weaknesses. UEFI toolkits are evolving rapidly, but UEFI has weaknesses: assume user is an ally trust TPM implicitly, and attached to computer hibernate file is unprotected (disk encryption protects against this) protection migrating from hardware to firmware delays in patching and whitelist updates will UEFI really be adopted by the mainstream (smartphone hardware support, bank support, apathetic consumer support) You Can't Buy Security: Building the Open Source InfoSec Program Boris Sverdlik, ISDPodcast.com co-host Boris talked about problems typical with current security audits. "IT Security" is an oxymoron—IT exists to enable buiness, uptime, utilization, reporting, but don't care about security—IT has conflict of interest. There's no Magic Bullet ("blinky box"), no one-size-fits-all solution (e.g., Intrusion Detection Systems (IDSs)). Regulations don't make you secure. The cloud is not secure (because of shared data and admin access). Defense and pen testing is not sexy. Auditors are not solution (security not a checklist)—what's needed is experience and adaptability—need soft skills. Step 1: First thing is to Google and learn the company end-to-end before you start. Get to know the management team (not IT team), meet as many people as you can. Don't use arbitrary values such as CISSP scores. Quantitive risk assessment is a myth (e.g. AV*EF-SLE). Learn different Business Units, legal/regulatory obligations, learn the business and where the money is made, verify company is protected from script kiddies (easy), learn sensitive information (IP, internal use only), and start with low-hanging fruit (customer service reps and social engineering). Step 2: Policies. Keep policies short and relevant. Generic SANS "security" boilerplate policies don't make sense and are not followed. Focus on acceptable use, data usage, communications, physical security. Step 3: Implementation: keep it simple stupid. Open source, although useful, is not free (implementation cost). Access controls with authentication & authorization for local and remote access. MS Windows has it, otherwise use OpenLDAP, OpenIAM, etc. Application security Everyone tries to reinvent the wheel—use existing static analysis tools. Review high-risk apps and major revisions. Don't run different risk level apps on same system. Assume host/client compromised and use app-level security control. Network security VLAN != segregated because there's too many workarounds. Use explicit firwall rules, active and passive network monitoring (snort is free), disallow end user access to production environment, have a proxy instead of direct Internet access. Also, SSL certificates are not good two-factor auth and SSL does not mean "safe." Operational Controls Have change, patch, asset, & vulnerability management (OSSI is free). For change management, always review code before pushing to production For logging, have centralized security logging for business-critical systems, separate security logging from administrative/IT logging, and lock down log (as it has everything). Monitor with OSSIM (open source). Use intrusion detection, but not just to fulfill a checkbox: build rules from a whitelist perspective (snort). OSSEC has 95% of what you need. Vulnerability management is a QA function when done right: OpenVas and Seccubus are free. Security awareness The reality is users will always click everything. Build real awareness, not compliance driven checkbox, and have it integrated into the culture. Pen test by crowd sourcing—test with logging COSSP http://www.cossp.org/ - Comprehensive Open Source Security Project What Journalists Want: The Investigative Reporters' Perspective on Hacking Dave Maas, San Diego CityBeat Jason Leopold, Truthout.org The difference between hackers and investigative journalists: For hackers, the motivation varies, but method is same, technological specialties. For investigative journalists, it's about one thing—The Story, and they need broad info-gathering skills. J-School in 60 Seconds: Generic formula: Person or issue of pubic interest, new info, or angle. Generic criteria: proximity, prominence, timeliness, human interest, oddity, or consequence. Media awareness of hackers and trends: journalists becoming extremely aware of hackers with congressional debates (privacy, data breaches), demand for data-mining Journalists, use of coding and web development for Journalists, and Journalists busted for hacking (Murdock). Info gathering by investigative journalists include Public records laws. Federal Freedom of Information Act (FOIA) is good, but slow. California Public Records Act is a lot stronger. FOIA takes forever because of foot-dragging—it helps to be specific. Often need to sue (especially FBI). CPRA is faster, and requests can be vague. Dumps and leaks (a la Wikileaks) Journalists want: leads, protecting ourselves, our sources, and adapting tools for news gathering (Google hacking). Anonomity is important to whistleblowers. They want no digital footprint left behind (e.g., email, web log). They don't trust encryption, want to feel safe and secure. Whistleblower laws are very weak—there's no upside for whistleblowers—they have to be very passionate to do it. Accessibility and Security or: How I Learned to Stop Worrying and Love the Halting Problem Anna Shubina, Dartmouth College Anna talked about how accessibility and security are related. Accessibility of digital content (not real world accessibility). mostly refers to blind users and screenreaders, for our purpose. Accessibility is about parsing documents, as are many security issues. "Rich" executable content causes accessibility to fail, and often causes security to fail. For example MS Word has executable format—it's not a document exchange format—more dangerous than PDF or HTML. Accessibility is often the first and maybe only sanity check with parsing. They have no choice because someone may want to read what you write. Google, for example, is very particular about web browser you use and are bad at supporting other browsers. Uses JavaScript instead of links, often requiring mouseover to display content. PDF is a security nightmare. Executible format, embedded flash, JavaScript, etc. 15 million lines of code. Google Chrome doesn't handle PDF correctly, causing several security bugs. PDF has an accessibility checker and PDF tagging, to help with accessibility. But no PDF checker checks for incorrect tags, untagged content, or validates lists or tables. None check executable content at all. The "Halting Problem" is: can one decide whether a program will ever stop? The answer, in general, is no (Rice's theorem). The same holds true for accessibility checkers. Language-theoretic Security says complicated data formats are hard to parse and cannot be solved due to the Halting Problem. W3C Web Accessibility Guidelines: "Perceivable, Operable, Understandable, Robust" Not much help though, except for "Robust", but here's some gems: * all information should be parsable (paraphrasing) * if not parsable, cannot be converted to alternate formats * maximize compatibility in new document formats Executible webpages are bad for security and accessibility. They say it's for a better web experience. But is it necessary to stuff web pages with JavaScript for a better experience? A good example is The Drudge Report—it has hand-written HTML with no JavaScript, yet drives a lot of web traffic due to good content. A bad example is Google News—hidden scrollbars, guessing user input. Solutions: Accessibility and security problems come from same source Expose "better user experience" myth Keep your corner of Internet parsable Remember "Halting Problem"—recognize false solutions (checking and verifying tools) Stop Patching, for Stronger PCI Compliance Adam Brand, protiviti @adamrbrand, http://www.picfun.com/ Adam talked about PCI compliance for retail sales. Take an example: for PCI compliance, 50% of Brian's time (a IT guy), 960 hours/year was spent patching POSs in 850 restaurants. Often applying some patches make no sense (like fixing a browser vulnerability on a server). "Scanner worship" is overuse of vulnerability scanners—it gives a warm and fuzzy and it's simple (red or green results—fix reds). Scanners give a false sense of security. In reality, breeches from missing patches are uncommon—more common problems are: default passwords, cleartext authentication, misconfiguration (firewall ports open). Patching Myths: Myth 1: install within 30 days of patch release (but PCI Â§6.1 allows a "risk-based approach" instead). Myth 2: vendor decides what's critical (also PCI Â§6.1). But Â§6.2 requires user ranking of vulnerabilities instead. Myth 3: scan and rescan until it passes. But PCI Â§11.2.1b says this applies only to high-risk vulnerabilities. Adam says good recommendations come from NIST 800-40. Instead use sane patching and focus on what's really important. From NIST 800-40: Proactive: Use a proactive vulnerability management process: use change control, configuration management, monitor file integrity. Monitor: start with NVD and other vulnerability alerts, not scanner results. Evaluate: public-facing system? workstation? internal server? (risk rank) Decide:on action and timeline Test: pre-test patches (stability, functionality, rollback) for change control Install: notify, change control, tickets McAfee Secure & Trustmarks — a Hacker's Best Friend Jay James, Shane MacDougall, Tactical Intelligence Inc., Canada "McAfee Secure Trustmark" is a website seal marketed by McAfee. A website gets this badge if they pass their remote scanning. The problem is a removal of trustmarks act as flags that you're vulnerable. Easy to view status change by viewing McAfee list on website or on Google. "Secure TrustGuard" is similar to McAfee. Jay and Shane wrote Perl scripts to gather sites from McAfee and search engines. If their certification image changes to a 1x1 pixel image, then they are longer certified. Their scripts take deltas of scans to see what changed daily. The bottom line is change in TrustGuard status is a flag for hackers to attack your site. Entire idea of seals is silly—you're raising a flag saying if you're vulnerable.

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A Taxonomy of Numerical Methods v1

- by JoshReuben

Numerical Analysis – When, What, (but not how) Once you understand the Math & know C++, Numerical Methods are basically blocks of iterative & conditional math code. I found the real trick was seeing the forest for the trees – knowing which method to use for which situation. Its pretty easy to get lost in the details – so I’ve tried to organize these methods in a way that I can quickly look this up. I’ve included links to detailed explanations and to C++ code examples. I’ve tried to classify Numerical methods in the following broad categories: Solving Systems of Linear Equations Solving Non-Linear Equations Iteratively Interpolation Curve Fitting Optimization Numerical Differentiation & Integration Solving ODEs Boundary Problems Solving EigenValue problems Enjoy – I did ! Solving Systems of Linear Equations Overview Solve sets of algebraic equations with x unknowns The set is commonly in matrix form Gauss-Jordan Elimination http://en.wikipedia.org/wiki/Gauss%E2%80%93Jordan_elimination C++: http://www.codekeep.net/snippets/623f1923-e03c-4636-8c92-c9dc7aa0d3c0.aspx Produces solution of the equations & the coefficient matrix Efficient, stable 2 steps: · Forward Elimination – matrix decomposition: reduce set to triangular form (0s below the diagonal) or row echelon form. If degenerate, then there is no solution · Backward Elimination –write the original matrix as the product of ints inverse matrix & its reduced row-echelon matrix à reduce set to row canonical form & use back-substitution to find the solution to the set Elementary ops for matrix decomposition: · Row multiplication · Row switching · Add multiples of rows to other rows Use pivoting to ensure rows are ordered for achieving triangular form LU Decomposition http://en.wikipedia.org/wiki/LU_decomposition C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-lu-decomposition-for-solving.html Represent the matrix as a product of lower & upper triangular matrices A modified version of GJ Elimination Advantage – can easily apply forward & backward elimination to solve triangular matrices Techniques: · Doolittle Method – sets the L matrix diagonal to unity · Crout Method - sets the U matrix diagonal to unity Note: both the L & U matrices share the same unity diagonal & can be stored compactly in the same matrix Gauss-Seidel Iteration http://en.wikipedia.org/wiki/Gauss%E2%80%93Seidel_method C++: http://www.nr.com/forum/showthread.php?t=722 Transform the linear set of equations into a single equation & then use numerical integration (as integration formulas have Sums, it is implemented iteratively). an optimization of Gauss-Jacobi: 1.5 times faster, requires 0.25 iterations to achieve the same tolerance Solving Non-Linear Equations Iteratively find roots of polynomials – there may be 0, 1 or n solutions for an n order polynomial use iterative techniques Iterative methods · used when there are no known analytical techniques · Requires set functions to be continuous & differentiable · Requires an initial seed value – choice is critical to convergence à conduct multiple runs with different starting points & then select best result · Systematic - iterate until diminishing returns, tolerance or max iteration conditions are met · bracketing techniques will always yield convergent solutions, non-bracketing methods may fail to converge Incremental method if a nonlinear function has opposite signs at 2 ends of a small interval x1 & x2, then there is likely to be a solution in their interval – solutions are detected by evaluating a function over interval steps, for a change in sign, adjusting the step size dynamically. Limitations – can miss closely spaced solutions in large intervals, cannot detect degenerate (coinciding) solutions, limited to functions that cross the x-axis, gives false positives for singularities Fixed point method http://en.wikipedia.org/wiki/Fixed-point_iteration C++: http://books.google.co.il/books?id=weYj75E_t6MC&pg=PA79&lpg=PA79&dq=fixed+point+method++c%2B%2B&source=bl&ots=LQ-5P_taoC&sig=lENUUIYBK53tZtTwNfHLy5PEWDk&hl=en&sa=X&ei=wezDUPW1J5DptQaMsIHQCw&redir_esc=y#v=onepage&q=fixed%20point%20method%20%20c%2B%2B&f=false Algebraically rearrange a solution to isolate a variable then apply incremental method Bisection method http://en.wikipedia.org/wiki/Bisection_method C++: http://numericalcomputing.wordpress.com/category/algorithms/ Bracketed - Select an initial interval, keep bisecting it ad midpoint into sub-intervals and then apply incremental method on smaller & smaller intervals – zoom in Adv: unaffected by function gradient à reliable Disadv: slow convergence False Position Method http://en.wikipedia.org/wiki/False_position_method C++: http://www.dreamincode.net/forums/topic/126100-bisection-and-false-position-methods/ Bracketed - Select an initial interval , & use the relative value of function at interval end points to select next sub-intervals (estimate how far between the end points the solution might be & subdivide based on this) Newton-Raphson method http://en.wikipedia.org/wiki/Newton's_method C++: http://www-users.cselabs.umn.edu/classes/Summer-2012/csci1113/index.php?page=./newt3 Also known as Newton's method Convenient, efficient Not bracketed – only a single initial guess is required to start iteration – requires an analytical expression for the first derivative of the function as input. Evaluates the function & its derivative at each step. Can be extended to the Newton MutiRoot method for solving multiple roots Can be easily applied to an of n-coupled set of non-linear equations – conduct a Taylor Series expansion of a function, dropping terms of order n, rewrite as a Jacobian matrix of PDs & convert to simultaneous linear equations !!! Secant Method http://en.wikipedia.org/wiki/Secant_method C++: http://forum.vcoderz.com/showthread.php?p=205230 Unlike N-R, can estimate first derivative from an initial interval (does not require root to be bracketed) instead of inputting it Since derivative is approximated, may converge slower. Is fast in practice as it does not have to evaluate the derivative at each step. Similar implementation to False Positive method Birge-Vieta Method http://mat.iitm.ac.in/home/sryedida/public_html/caimna/transcendental/polynomial%20methods/bv%20method.html C++: http://books.google.co.il/books?id=cL1boM2uyQwC&pg=SA3-PA51&lpg=SA3-PA51&dq=Birge-Vieta+Method+c%2B%2B&source=bl&ots=QZmnDTK3rC&sig=BPNcHHbpR_DKVoZXrLi4nVXD-gg&hl=en&sa=X&ei=R-_DUK2iNIjzsgbE5ID4Dg&redir_esc=y#v=onepage&q=Birge-Vieta%20Method%20c%2B%2B&f=false combines Horner's method of polynomial evaluation (transforming into lesser degree polynomials that are more computationally efficient to process) with Newton-Raphson to provide a computational speed-up Interpolation Overview Construct new data points for as close as possible fit within range of a discrete set of known points (that were obtained via sampling, experimentation) Use Taylor Series Expansion of a function f(x) around a specific value for x Linear Interpolation http://en.wikipedia.org/wiki/Linear_interpolation C++: http://www.hamaluik.com/?p=289 Straight line between 2 points à concatenate interpolants between each pair of data points Bilinear Interpolation http://en.wikipedia.org/wiki/Bilinear_interpolation C++: http://supercomputingblog.com/graphics/coding-bilinear-interpolation/2/ Extension of the linear function for interpolating functions of 2 variables – perform linear interpolation first in 1 direction, then in another. Used in image processing – e.g. texture mapping filter. Uses 4 vertices to interpolate a value within a unit cell. Lagrange Interpolation http://en.wikipedia.org/wiki/Lagrange_polynomial C++: http://www.codecogs.com/code/maths/approximation/interpolation/lagrange.php For polynomials Requires recomputation for all terms for each distinct x value – can only be applied for small number of nodes Numerically unstable Barycentric Interpolation http://epubs.siam.org/doi/pdf/10.1137/S0036144502417715 C++: http://www.gamedev.net/topic/621445-barycentric-coordinates-c-code-check/ Rearrange the terms in the equation of the Legrange interpolation by defining weight functions that are independent of the interpolated value of x Newton Divided Difference Interpolation http://en.wikipedia.org/wiki/Newton_polynomial C++: http://jee-appy.blogspot.co.il/2011/12/newton-divided-difference-interpolation.html Hermite Divided Differences: Interpolation polynomial approximation for a given set of data points in the NR form - divided differences are used to approximately calculate the various differences. For a given set of 3 data points , fit a quadratic interpolant through the data Bracketed functions allow Newton divided differences to be calculated recursively Difference table Cubic Spline Interpolation http://en.wikipedia.org/wiki/Spline_interpolation C++: https://www.marcusbannerman.co.uk/index.php/home/latestarticles/42-articles/96-cubic-spline-class.html Spline is a piecewise polynomial Provides smoothness – for interpolations with significantly varying data Use weighted coefficients to bend the function to be smooth & its 1st & 2nd derivatives are continuous through the edge points in the interval Curve Fitting A generalization of interpolating whereby given data points may contain noise à the curve does not necessarily pass through all the points Least Squares Fit http://en.wikipedia.org/wiki/Least_squares C++: http://www.ccas.ru/mmes/educat/lab04k/02/least-squares.c Residual – difference between observed value & expected value Model function is often chosen as a linear combination of the specified functions Determines: A) The model instance in which the sum of squared residuals has the least value B) param values for which model best fits data Straight Line Fit Linear correlation between independent variable and dependent variable Linear Regression http://en.wikipedia.org/wiki/Linear_regression C++: http://www.oocities.org/david_swaim/cpp/linregc.htm Special case of statistically exact extrapolation Leverage least squares Given a basis function, the sum of the residuals is determined and the corresponding gradient equation is expressed as a set of normal linear equations in matrix form that can be solved (e.g. using LU Decomposition) Can be weighted - Drop the assumption that all errors have the same significance –-> confidence of accuracy is different for each data point. Fit the function closer to points with higher weights Polynomial Fit - use a polynomial basis function Moving Average http://en.wikipedia.org/wiki/Moving_average C++: http://www.codeproject.com/Articles/17860/A-Simple-Moving-Average-Algorithm Used for smoothing (cancel fluctuations to highlight longer-term trends & cycles), time series data analysis, signal processing filters Replace each data point with average of neighbors. Can be simple (SMA), weighted (WMA), exponential (EMA). Lags behind latest data points – extra weight can be given to more recent data points. Weights can decrease arithmetically or exponentially according to distance from point. Parameters: smoothing factor, period, weight basis Optimization Overview Given function with multiple variables, find Min (or max by minimizing –f(x)) Iterative approach Efficient, but not necessarily reliable Conditions: noisy data, constraints, non-linear models Detection via sign of first derivative - Derivative of saddle points will be 0 Local minima Bisection method Similar method for finding a root for a non-linear equation Start with an interval that contains a minimum Golden Search method http://en.wikipedia.org/wiki/Golden_section_search C++: http://www.codecogs.com/code/maths/optimization/golden.php Bisect intervals according to golden ratio 0.618.. Achieves reduction by evaluating a single function instead of 2 Newton-Raphson Method Brent method http://en.wikipedia.org/wiki/Brent's_method C++: http://people.sc.fsu.edu/~jburkardt/cpp_src/brent/brent.cpp Based on quadratic or parabolic interpolation – if the function is smooth & parabolic near to the minimum, then a parabola fitted through any 3 points should approximate the minima – fails when the 3 points are collinear , in which case the denominator is 0 Simplex Method http://en.wikipedia.org/wiki/Simplex_algorithm C++: http://www.codeguru.com/cpp/article.php/c17505/Simplex-Optimization-Algorithm-and-Implemetation-in-C-Programming.htm Find the global minima of any multi-variable function Direct search – no derivatives required At each step it maintains a non-degenerative simplex – a convex hull of n+1 vertices. Obtains the minimum for a function with n variables by evaluating the function at n-1 points, iteratively replacing the point of worst result with the point of best result, shrinking the multidimensional simplex around the best point. Point replacement involves expanding & contracting the simplex near the worst value point to determine a better replacement point Oscillation can be avoided by choosing the 2nd worst result Restart if it gets stuck Parameters: contraction & expansion factors Simulated Annealing http://en.wikipedia.org/wiki/Simulated_annealing C++: http://code.google.com/p/cppsimulatedannealing/ Analogy to heating & cooling metal to strengthen its structure Stochastic method – apply random permutation search for global minima - Avoid entrapment in local minima via hill climbing Heating schedule - Annealing schedule params: temperature, iterations at each temp, temperature delta Cooling schedule – can be linear, step-wise or exponential Differential Evolution http://en.wikipedia.org/wiki/Differential_evolution C++: http://www.amichel.com/de/doc/html/ More advanced stochastic methods analogous to biological processes: Genetic algorithms, evolution strategies Parallel direct search method against multiple discrete or continuous variables Initial population of variable vectors chosen randomly – if weighted difference vector of 2 vectors yields a lower objective function value then it replaces the comparison vector Many params: #parents, #variables, step size, crossover constant etc Convergence is slow – many more function evaluations than simulated annealing Numerical Differentiation Overview 2 approaches to finite difference methods: · A) approximate function via polynomial interpolation then differentiate · B) Taylor series approximation – additionally provides error estimate Finite Difference methods http://en.wikipedia.org/wiki/Finite_difference_method C++: http://www.wpi.edu/Pubs/ETD/Available/etd-051807-164436/unrestricted/EAMPADU.pdf Find differences between high order derivative values - Approximate differential equations by finite differences at evenly spaced data points Based on forward & backward Taylor series expansion of f(x) about x plus or minus multiples of delta h. Forward / backward difference - the sums of the series contains even derivatives and the difference of the series contains odd derivatives – coupled equations that can be solved. Provide an approximation of the derivative within a O(h^2) accuracy There is also central difference & extended central difference which has a O(h^4) accuracy Richardson Extrapolation http://en.wikipedia.org/wiki/Richardson_extrapolation C++: http://mathscoding.blogspot.co.il/2012/02/introduction-richardson-extrapolation.html A sequence acceleration method applied to finite differences Fast convergence, high accuracy O(h^4) Derivatives via Interpolation Cannot apply Finite Difference method to discrete data points at uneven intervals – so need to approximate the derivative of f(x) using the derivative of the interpolant via 3 point Lagrange Interpolation Note: the higher the order of the derivative, the lower the approximation precision Numerical Integration Estimate finite & infinite integrals of functions More accurate procedure than numerical differentiation Use when it is not possible to obtain an integral of a function analytically or when the function is not given, only the data points are Newton Cotes Methods http://en.wikipedia.org/wiki/Newton%E2%80%93Cotes_formulas C++: http://www.siafoo.net/snippet/324 For equally spaced data points Computationally easy – based on local interpolation of n rectangular strip areas that is piecewise fitted to a polynomial to get the sum total area Evaluate the integrand at n+1 evenly spaced points – approximate definite integral by Sum Weights are derived from Lagrange Basis polynomials Leverage Trapezoidal Rule for default 2nd formulas, Simpson 1/3 Rule for substituting 3 point formulas, Simpson 3/8 Rule for 4 point formulas. For 4 point formulas use Bodes Rule. Higher orders obtain more accurate results Trapezoidal Rule uses simple area, Simpsons Rule replaces the integrand f(x) with a quadratic polynomial p(x) that uses the same values as f(x) for its end points, but adds a midpoint Romberg Integration http://en.wikipedia.org/wiki/Romberg's_method C++: http://code.google.com/p/romberg-integration/downloads/detail?name=romberg.cpp&can=2&q= Combines trapezoidal rule with Richardson Extrapolation Evaluates the integrand at equally spaced points The integrand must have continuous derivatives Each R(n,m) extrapolation uses a higher order integrand polynomial replacement rule (zeroth starts with trapezoidal) à a lower triangular matrix set of equation coefficients where the bottom right term has the most accurate approximation. The process continues until the difference between 2 successive diagonal terms becomes sufficiently small. Gaussian Quadrature http://en.wikipedia.org/wiki/Gaussian_quadrature C++: http://www.alglib.net/integration/gaussianquadratures.php Data points are chosen to yield best possible accuracy – requires fewer evaluations Ability to handle singularities, functions that are difficult to evaluate The integrand can include a weighting function determined by a set of orthogonal polynomials. Points & weights are selected so that the integrand yields the exact integral if f(x) is a polynomial of degree <= 2n+1 Techniques (basically different weighting functions): · Gauss-Legendre Integration w(x)=1 · Gauss-Laguerre Integration w(x)=e^-x · Gauss-Hermite Integration w(x)=e^-x^2 · Gauss-Chebyshev Integration w(x)= 1 / Sqrt(1-x^2) Solving ODEs Use when high order differential equations cannot be solved analytically Evaluated under boundary conditions RK for systems – a high order differential equation can always be transformed into a coupled first order system of equations Euler method http://en.wikipedia.org/wiki/Euler_method C++: http://rosettacode.org/wiki/Euler_method First order Runge–Kutta method. Simple recursive method – given an initial value, calculate derivative deltas. Unstable & not very accurate (O(h) error) – not used in practice A first-order method - the local error (truncation error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size In evolving solution between data points xn & xn+1, only evaluates derivatives at beginning of interval xn à asymmetric at boundaries Higher order Runge Kutta http://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods C++: http://www.dreamincode.net/code/snippet1441.htm 2nd & 4th order RK - Introduces parameterized midpoints for more symmetric solutions à accuracy at higher computational cost Adaptive RK – RK-Fehlberg – estimate the truncation at each integration step & automatically adjust the step size to keep error within prescribed limits. At each step 2 approximations are compared – if in disagreement to a specific accuracy, the step size is reduced Boundary Value Problems Where solution of differential equations are located at 2 different values of the independent variable x à more difficult, because cannot just start at point of initial value – there may not be enough starting conditions available at the end points to produce a unique solution An n-order equation will require n boundary conditions – need to determine the missing n-1 conditions which cause the given conditions at the other boundary to be satisfied Shooting Method http://en.wikipedia.org/wiki/Shooting_method C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-shooting-method-for-solving.html Iteratively guess the missing values for one end & integrate, then inspect the discrepancy with the boundary values of the other end to adjust the estimate Given the starting boundary values u1 & u2 which contain the root u, solve u given the false position method (solving the differential equation as an initial value problem via 4th order RK), then use u to solve the differential equations. Finite Difference Method For linear & non-linear systems Higher order derivatives require more computational steps – some combinations for boundary conditions may not work though Improve the accuracy by increasing the number of mesh points Solving EigenValue Problems An eigenvalue can substitute a matrix when doing matrix multiplication à convert matrix multiplication into a polynomial EigenValue For a given set of equations in matrix form, determine what are the solution eigenvalue & eigenvectors Similar Matrices - have same eigenvalues. Use orthogonal similarity transforms to reduce a matrix to diagonal form from which eigenvalue(s) & eigenvectors can be computed iteratively Jacobi method http://en.wikipedia.org/wiki/Jacobi_method C++: http://people.sc.fsu.edu/~jburkardt/classes/acs2_2008/openmp/jacobi/jacobi.html Robust but Computationally intense – use for small matrices < 10x10 Power Iteration http://en.wikipedia.org/wiki/Power_iteration For any given real symmetric matrix, generate the largest single eigenvalue & its eigenvectors Simplest method – does not compute matrix decomposition à suitable for large, sparse matrices Inverse Iteration Variation of power iteration method – generates the smallest eigenvalue from the inverse matrix Rayleigh Method http://en.wikipedia.org/wiki/Rayleigh's_method_of_dimensional_analysis Variation of power iteration method Rayleigh Quotient Method Variation of inverse iteration method Matrix Tri-diagonalization Method Use householder algorithm to reduce an NxN symmetric matrix to a tridiagonal real symmetric matrix vua N-2 orthogonal transforms Whats Next Outside of Numerical Methods there are lots of different types of algorithms that I’ve learned over the decades: Data Mining – (I covered this briefly in a previous post: http://geekswithblogs.net/JoshReuben/archive/2007/12/31/ssas-dm-algorithms.aspx ) Search & Sort Routing Problem Solving Logical Theorem Proving Planning Probabilistic Reasoning Machine Learning Solvers (eg MIP) Bioinformatics (Sequence Alignment, Protein Folding) Quant Finance (I read Wilmott’s books – interesting) Sooner or later, I’ll cover the above topics as well.

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Unable to boot Windows 7 after installing Ubuntu

- by Devendra

I have Windows 7 on my machine and then installed Ubuntu 12.04 using a live CD. I can see both Windows 7 and Ubuntu in the grub menu, but when I select Windows 7 it shows a black screen for about 2 seconds and the returns to the Grub menu. But if I select Ubuntu it's working fine. This is the contents of the boot-repair log: Boot Info Script 0.61.full + Boot-Repair extra info [Boot-Info November 20th 2012] ============================= Boot Info Summary: =============================== => Grub2 (v2.00) is installed in the MBR of /dev/sda and looks at sector 1 of the same hard drive for core.img. core.img is at this location and looks in partition 1 for (,msdos6)/boot/grub. sda1: __________________________________________________________________________ File system: ntfs Boot sector type: Grub2 (v1.99-2.00) Boot sector info: Grub2 (v2.00) is installed in the boot sector of sda1 and looks at sector 388911128 of the same hard drive for core.img. core.img is at this location and looks in partition 1 for (,msdos6)/boot/grub. No errors found in the Boot Parameter Block. Operating System: Windows 7 Boot files: /bootmgr /Boot/BCD /Windows/System32/winload.exe sda2: __________________________________________________________________________ File system: ntfs Boot sector type: Windows Vista/7: NTFS Boot sector info: No errors found in the Boot Parameter Block. Operating System: Boot files: sda3: __________________________________________________________________________ File system: ntfs Boot sector type: Windows Vista/7: NTFS Boot sector info: No errors found in the Boot Parameter Block. Operating System: Boot files: sda4: __________________________________________________________________________ File system: Extended Partition Boot sector type: - Boot sector info: sda5: __________________________________________________________________________ File system: ntfs Boot sector type: Windows Vista/7: NTFS Boot sector info: According to the info in the boot sector, sda5 starts at sector 2048. Operating System: Boot files: sda6: __________________________________________________________________________ File system: ext4 Boot sector type: - Boot sector info: Operating System: Ubuntu 12.10 Boot files: /boot/grub/grub.cfg /etc/fstab /boot/grub/i386-pc/core.img sda7: __________________________________________________________________________ File system: swap Boot sector type: - Boot sector info: ============================ Drive/Partition Info: ============================= Drive: sda _____________________________________________________________________ Disk /dev/sda: 750.2 GB, 750156374016 bytes 255 heads, 63 sectors/track, 91201 cylinders, total 1465149168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes Partition Boot Start Sector End Sector # of Sectors Id System /dev/sda1 * 206,848 146,802,687 146,595,840 7 NTFS / exFAT / HPFS /dev/sda2 147,007,488 293,623,807 146,616,320 7 NTFS / exFAT / HPFS /dev/sda3 293,623,808 332,820,613 39,196,806 7 NTFS / exFAT / HPFS /dev/sda4 332,822,526 1,465,145,343 1,132,322,818 f W95 Extended (LBA) /dev/sda5 461,342,720 1,465,145,343 1,003,802,624 7 NTFS / exFAT / HPFS /dev/sda6 332,822,528 453,171,199 120,348,672 83 Linux /dev/sda7 453,173,248 461,338,623 8,165,376 82 Linux swap / Solaris "blkid" output: ________________________________________________________________ Device UUID TYPE LABEL /dev/sda1 F6AE2C13AE2BCB47 ntfs /dev/sda2 DC2273012272DFC6 ntfs /dev/sda3 1E76E43376E40D79 ntfs New Volume /dev/sda5 5ED60ACDD60AA57D ntfs /dev/sda6 9e70fd16-b48b-4f88-adcf-e443aef83124 ext4 /dev/sda7 52f3dd94-6be7-4a7b-a3ae-f43eb8810483 swap ================================ Mount points: ================================= Device Mount_Point Type Options /dev/sda6 / ext4 (rw,errors=remount-ro) =========================== sda6/boot/grub/grub.cfg: =========================== -------------------------------------------------------------------------------- # # DO NOT EDIT THIS FILE # # It is automatically generated by grub-mkconfig using templates # from /etc/grub.d and settings from /etc/default/grub # ### BEGIN /etc/grub.d/00_header ### if [ -s $prefix/grubenv ]; then set have_grubenv=true load_env fi set default="0" if [ x"${feature_menuentry_id}" = xy ]; then menuentry_id_option="--id" else menuentry_id_option="" fi export menuentry_id_option if [ "${prev_saved_entry}" ]; then set saved_entry="${prev_saved_entry}" save_env saved_entry set prev_saved_entry= save_env prev_saved_entry set boot_once=true fi function savedefault { if [ -z "${boot_once}" ]; then saved_entry="${chosen}" save_env saved_entry fi } function recordfail { set recordfail=1 if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi } function load_video { if [ x$feature_all_video_module = xy ]; then insmod all_video else insmod efi_gop insmod efi_uga insmod ieee1275_fb insmod vbe insmod vga insmod video_bochs insmod video_cirrus fi } if [ x$feature_default_font_path = xy ] ; then font=unicode else insmod part_msdos insmod ext2 set root='hd0,msdos6' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos6 --hint-efi=hd0,msdos6 --hint-baremetal=ahci0,msdos6 9e70fd16-b48b-4f88-adcf-e443aef83124 else search --no-floppy --fs-uuid --set=root 9e70fd16-b48b-4f88-adcf-e443aef83124 fi font="/usr/share/grub/unicode.pf2" fi if loadfont $font ; then set gfxmode=auto load_video insmod gfxterm set locale_dir=$prefix/locale set lang=en_IN insmod gettext fi terminal_output gfxterm if [ "${recordfail}" = 1 ]; then set timeout=10 else set timeout=10 fi ### END /etc/grub.d/00_header ### ### BEGIN /etc/grub.d/05_debian_theme ### set menu_color_normal=white/black set menu_color_highlight=black/light-gray if background_color 44,0,30; then clear fi ### END /etc/grub.d/05_debian_theme ### ### BEGIN /etc/grub.d/10_linux ### function gfxmode { set gfxpayload="${1}" if [ "${1}" = "keep" ]; then set vt_handoff=vt.handoff=7 else set vt_handoff= fi } if [ "${recordfail}" != 1 ]; then if [ -e ${prefix}/gfxblacklist.txt ]; then if hwmatch ${prefix}/gfxblacklist.txt 3; then if [ ${match} = 0 ]; then set linux_gfx_mode=keep else set linux_gfx_mode=text fi else set linux_gfx_mode=text fi else set linux_gfx_mode=keep fi else set linux_gfx_mode=text fi export linux_gfx_mode if [ "${linux_gfx_mode}" != "text" ]; then load_video; fi menuentry 'Ubuntu' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-9e70fd16-b48b-4f88-adcf-e443aef83124' { recordfail gfxmode $linux_gfx_mode insmod gzio insmod part_msdos insmod ext2 set root='hd0,msdos6' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos6 --hint-efi=hd0,msdos6 --hint-baremetal=ahci0,msdos6 9e70fd16-b48b-4f88-adcf-e443aef83124 else search --no-floppy --fs-uuid --set=root 9e70fd16-b48b-4f88-adcf-e443aef83124 fi linux /boot/vmlinuz-3.5.0-17-generic root=UUID=9e70fd16-b48b-4f88-adcf-e443aef83124 ro quiet splash $vt_handoff initrd /boot/initrd.img-3.5.0-17-generic } submenu 'Advanced options for Ubuntu' $menuentry_id_option 'gnulinux-advanced-9e70fd16-b48b-4f88-adcf-e443aef83124' { menuentry 'Ubuntu, with Linux 3.5.0-17-generic' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-3.5.0-17-generic-advanced-9e70fd16-b48b-4f88-adcf-e443aef83124' { recordfail gfxmode $linux_gfx_mode insmod gzio insmod part_msdos insmod ext2 set root='hd0,msdos6' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos6 --hint-efi=hd0,msdos6 --hint-baremetal=ahci0,msdos6 9e70fd16-b48b-4f88-adcf-e443aef83124 else search --no-floppy --fs-uuid --set=root 9e70fd16-b48b-4f88-adcf-e443aef83124 fi echo 'Loading Linux 3.5.0-17-generic ...' linux /boot/vmlinuz-3.5.0-17-generic root=UUID=9e70fd16-b48b-4f88-adcf-e443aef83124 ro quiet splash $vt_handoff echo 'Loading initial ramdisk ...' initrd /boot/initrd.img-3.5.0-17-generic } menuentry 'Ubuntu, with Linux 3.5.0-17-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-3.5.0-17-generic-recovery-9e70fd16-b48b-4f88-adcf-e443aef83124' { recordfail insmod gzio insmod part_msdos insmod ext2 set root='hd0,msdos6' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos6 --hint-efi=hd0,msdos6 --hint-baremetal=ahci0,msdos6 9e70fd16-b48b-4f88-adcf-e443aef83124 else search --no-floppy --fs-uuid --set=root 9e70fd16-b48b-4f88-adcf-e443aef83124 fi echo 'Loading Linux 3.5.0-17-generic ...' linux /boot/vmlinuz-3.5.0-17-generic root=UUID=9e70fd16-b48b-4f88-adcf-e443aef83124 ro recovery nomodeset echo 'Loading initial ramdisk ...' initrd /boot/initrd.img-3.5.0-17-generic } } ### END /etc/grub.d/10_linux ### ### BEGIN /etc/grub.d/20_linux_xen ### ### END /etc/grub.d/20_linux_xen ### ### BEGIN /etc/grub.d/20_memtest86+ ### menuentry "Memory test (memtest86+)" { insmod part_msdos insmod ext2 set root='hd0,msdos6' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos6 --hint-efi=hd0,msdos6 --hint-baremetal=ahci0,msdos6 9e70fd16-b48b-4f88-adcf-e443aef83124 else search --no-floppy --fs-uuid --set=root 9e70fd16-b48b-4f88-adcf-e443aef83124 fi linux16 /boot/memtest86+.bin } menuentry "Memory test (memtest86+, serial console 115200)" { insmod part_msdos insmod ext2 set root='hd0,msdos6' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos6 --hint-efi=hd0,msdos6 --hint-baremetal=ahci0,msdos6 9e70fd16-b48b-4f88-adcf-e443aef83124 else search --no-floppy --fs-uuid --set=root 9e70fd16-b48b-4f88-adcf-e443aef83124 fi linux16 /boot/memtest86+.bin console=ttyS0,115200n8 } ### END /etc/grub.d/20_memtest86+ ### ### BEGIN /etc/grub.d/30_os-prober ### menuentry 'Windows 7 (loader) (on /dev/sda1)' --class windows --class os $menuentry_id_option 'osprober-chain-F6AE2C13AE2BCB47' { insmod part_msdos insmod ntfs set root='hd0,msdos1' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 F6AE2C13AE2BCB47 else search --no-floppy --fs-uuid --set=root F6AE2C13AE2BCB47 fi chainloader +1 } ### END /etc/grub.d/30_os-prober ### ### BEGIN /etc/grub.d/30_uefi-firmware ### ### END /etc/grub.d/30_uefi-firmware ### ### BEGIN /etc/grub.d/40_custom ### # This file provides an easy way to add custom menu entries. Simply type the # menu entries you want to add after this comment. Be careful not to change # the 'exec tail' line above. ### END /etc/grub.d/40_custom ### ### BEGIN /etc/grub.d/41_custom ### if [ -f ${config_directory}/custom.cfg ]; then source ${config_directory}/custom.cfg elif [ -z "${config_directory}" -a -f $prefix/custom.cfg ]; then source $prefix/custom.cfg; fi ### END /etc/grub.d/41_custom ### -------------------------------------------------------------------------------- =============================== sda6/etc/fstab: ================================ -------------------------------------------------------------------------------- # /etc/fstab: static file system information. # # Use 'blkid' to print the universally unique identifier for a # device; this may be used with UUID= as a more robust way to name devices # that works even if disks are added and removed. See fstab(5). # # <file system> <mount point> <type> <options> <dump> <pass> # / was on /dev/sda6 during installation UUID=9e70fd16-b48b-4f88-adcf-e443aef83124 / ext4 errors=remount-ro 0 1 # swap was on /dev/sda7 during installation UUID=52f3dd94-6be7-4a7b-a3ae-f43eb8810483 none swap sw 0 0 -------------------------------------------------------------------------------- =================== sda6: Location of files loaded by Grub: ==================== GiB - GB File Fragment(s) 162.831275940 = 174.838751232 boot/grub/grub.cfg 1 163.036647797 = 175.059267584 boot/initrd.img-3.5.0-17-generic 1 206.871749878 = 222.126850048 boot/vmlinuz-3.5.0-17-generic 1 163.036647797 = 175.059267584 initrd.img 1 163.036647797 = 175.059267584 initrd.img.old 1 206.871749878 = 222.126850048 vmlinuz 1 =============================== StdErr Messages: =============================== cat: write error: Broken pipe cat: write error: Broken pipe ADDITIONAL INFORMATION : =================== log of boot-repair 2012-12-11__00h59 =================== boot-repair version : 3.195~ppa28~quantal boot-sav version : 3.195~ppa28~quantal glade2script version : 3.2.2~ppa45~quantal boot-sav-extra version : 3.195~ppa28~quantal boot-repair is executed in installed-session (Ubuntu 12.10, quantal, Ubuntu, x86_64) CPU op-mode(s): 32-bit, 64-bit BOOT_IMAGE=/boot/vmlinuz-3.5.0-17-generic root=UUID=9e70fd16-b48b-4f88-adcf-e443aef83124 ro quiet splash vt.handoff=7 =================== os-prober: /dev/sda6:The OS now in use - Ubuntu 12.10 CurrentSession:linux /dev/sda1:Windows 7 (loader):Windows:chain =================== blkid: /dev/sda1: UUID="F6AE2C13AE2BCB47" TYPE="ntfs" /dev/sda2: UUID="DC2273012272DFC6" TYPE="ntfs" /dev/sda3: LABEL="New Volume" UUID="1E76E43376E40D79" TYPE="ntfs" /dev/sda5: UUID="5ED60ACDD60AA57D" TYPE="ntfs" /dev/sda6: UUID="9e70fd16-b48b-4f88-adcf-e443aef83124" TYPE="ext4" /dev/sda7: UUID="52f3dd94-6be7-4a7b-a3ae-f43eb8810483" TYPE="swap" 1 disks with OS, 2 OS : 1 Linux, 0 MacOS, 1 Windows, 0 unknown type OS. Warning: extended partition does not start at a cylinder boundary. DOS and Linux will interpret the contents differently. =================== /etc/default/grub : # If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 #GRUB_HIDDEN_TIMEOUT=0 GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" GRUB_CMDLINE_LINUX="" # Uncomment to enable BadRAM filtering, modify to suit your needs # This works with Linux (no patch required) and with any kernel that obtains # the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...) #GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef" # Uncomment to disable graphical terminal (grub-pc only) #GRUB_TERMINAL=console # The resolution used on graphical terminal # note that you can use only modes which your graphic card supports via VBE # you can see them in real GRUB with the command `vbeinfo' #GRUB_GFXMODE=640x480 # Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux #GRUB_DISABLE_LINUX_UUID=true # Uncomment to disable generation of recovery mode menu entries #GRUB_DISABLE_RECOVERY="true" # Uncomment to get a beep at grub start #GRUB_INIT_TUNE="480 440 1" =================== /etc/grub.d/ : drwxr-xr-x 2 root root 4096 Oct 17 20:29 grub.d total 72 -rwxr-xr-x 1 root root 7541 Oct 14 23:06 00_header -rwxr-xr-x 1 root root 5488 Oct 4 15:00 05_debian_theme -rwxr-xr-x 1 root root 10891 Oct 14 23:06 10_linux -rwxr-xr-x 1 root root 10258 Oct 14 23:06 20_linux_xen -rwxr-xr-x 1 root root 1688 Oct 11 19:40 20_memtest86+ -rwxr-xr-x 1 root root 10976 Oct 14 23:06 30_os-prober -rwxr-xr-x 1 root root 1426 Oct 14 23:06 30_uefi-firmware -rwxr-xr-x 1 root root 214 Oct 14 23:06 40_custom -rwxr-xr-x 1 root root 216 Oct 14 23:06 41_custom -rw-r--r-- 1 root root 483 Oct 14 23:06 README =================== UEFI/Legacy mode: This installed-session is not in EFI-mode. EFI in dmesg. Please report this message to [email protected] [ 0.000000] ACPI: UEFI 00000000bafe7000 0003E (v01 DELL QA09 00000002 PTL 00000002) [ 0.000000] ACPI: UEFI 00000000bafe6000 00042 (v01 PTL COMBUF 00000001 PTL 00000001) [ 0.000000] ACPI: UEFI 00000000bafe3000 00256 (v01 DELL QA09 00000002 PTL 00000002) SecureBoot disabled. =================== PARTITIONS & DISKS: sda6 : sda, not-sepboot, grubenv-ok grub2, grub-pc , update-grub, 64, with-boot, is-os, not--efi--part, fstab-without-boot, fstab-without-efi, no-nt, no-winload, no-recov-nor-hid, no-bmgr, notwinboot, apt-get, grub-install, with--usr, fstab-without-usr, not-sep-usr, standard, farbios, . sda1 : sda, not-sepboot, no-grubenv nogrub, no-docgrub, no-update-grub, 32, no-boot, is-os, not--efi--part, part-has-no-fstab, part-has-no-fstab, no-nt, haswinload, no-recov-nor-hid, bootmgr, is-winboot, nopakmgr, nogrubinstall, no---usr, part-has-no-fstab, not-sep-usr, standard, not-far, /mnt/boot-sav/sda1. sda2 : sda, not-sepboot, no-grubenv nogrub, no-docgrub, no-update-grub, 32, no-boot, no-os, not--efi--part, part-has-no-fstab, part-has-no-fstab, no-nt, no-winload, no-recov-nor-hid, no-bmgr, notwinboot, nopakmgr, nogrubinstall, no---usr, part-has-no-fstab, not-sep-usr, standard, farbios, /mnt/boot-sav/sda2. sda3 : sda, not-sepboot, no-grubenv nogrub, no-docgrub, no-update-grub, 32, no-boot, no-os, not--efi--part, part-has-no-fstab, part-has-no-fstab, no-nt, no-winload, no-recov-nor-hid, no-bmgr, notwinboot, nopakmgr, nogrubinstall, no---usr, part-has-no-fstab, not-sep-usr, standard, farbios, /mnt/boot-sav/sda3. sda5 : sda, not-sepboot, no-grubenv nogrub, no-docgrub, no-update-grub, 32, no-boot, no-os, not--efi--part, part-has-no-fstab, part-has-no-fstab, no-nt, no-winload, no-recov-nor-hid, no-bmgr, notwinboot, nopakmgr, nogrubinstall, no---usr, part-has-no-fstab, not-sep-usr, standard, farbios, /mnt/boot-sav/sda5. sda : not-GPT, BIOSboot-not-needed, has-no-EFIpart, not-usb, has-os, 2048 sectors * 512 bytes =================== parted -l: Model: ATA WDC WD7500BPKT-7 (scsi) Disk /dev/sda: 750GB Sector size (logical/physical): 512B/4096B Partition Table: msdos Number Start End Size Type File system Flags 1 106MB 75.2GB 75.1GB primary ntfs boot 2 75.3GB 150GB 75.1GB primary ntfs 3 150GB 170GB 20.1GB primary ntfs 4 170GB 750GB 580GB extended lba 6 170GB 232GB 61.6GB logical ext4 7 232GB 236GB 4181MB logical linux-swap(v1) 5 236GB 750GB 514GB logical ntfs =================== parted -lm: BYT; /dev/sda:750GB:scsi:512:4096:msdos:ATA WDC WD7500BPKT-7; 1:106MB:75.2GB:75.1GB:ntfs::boot; 2:75.3GB:150GB:75.1GB:ntfs::; 3:150GB:170GB:20.1GB:ntfs::; 4:170GB:750GB:580GB:::lba; 6:170GB:232GB:61.6GB:ext4::; 7:232GB:236GB:4181MB:linux-swap(v1)::; 5:236GB:750GB:514GB:ntfs::; =================== mount: /dev/sda6 on / type ext4 (rw,errors=remount-ro) proc on /proc type proc (rw,noexec,nosuid,nodev) sysfs on /sys type sysfs (rw,noexec,nosuid,nodev) none on /sys/fs/fuse/connections type fusectl (rw) none on /sys/kernel/debug type debugfs (rw) none on /sys/kernel/security type securityfs (rw) udev on /dev type devtmpfs (rw,mode=0755) devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620) tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755) none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880) none on /run/shm type tmpfs (rw,nosuid,nodev) none on /run/user type tmpfs (rw,noexec,nosuid,nodev,size=104857600,mode=0755) gvfsd-fuse on /run/user/dev/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,user=dev) /dev/sda1 on /mnt/boot-sav/sda1 type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096) /dev/sda2 on /mnt/boot-sav/sda2 type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096) /dev/sda3 on /mnt/boot-sav/sda3 type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096) /dev/sda5 on /mnt/boot-sav/sda5 type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096) =================== ls: /sys/block/sda (filtered): alignment_offset bdi capability dev device discard_alignment events events_async events_poll_msecs ext_range holders inflight power queue range removable ro sda1 sda2 sda3 sda4 sda5 sda6 sda7 size slaves stat subsystem trace uevent /sys/block/sr0 (filtered): alignment_offset bdi capability dev device discard_alignment events events_async events_poll_msecs ext_range holders inflight power queue range removable ro size slaves stat subsystem trace uevent /dev (filtered): alarm ashmem autofs binder block bsg btrfs-control bus cdrom cdrw char console core cpu cpu_dma_latency disk dri dvd dvdrw ecryptfs fb0 fb1 fd full fuse hpet input kmsg kvm log mapper mcelog mei mem net network_latency network_throughput null oldmem port ppp psaux ptmx pts random rfkill rtc rtc0 sda sda1 sda2 sda3 sda4 sda5 sda6 sda7 sg0 sg1 shm snapshot snd sr0 stderr stdin stdout uinput urandom v4l vga_arbiter vhost-net video0 zero ls /dev/mapper: control =================== df -Th: Filesystem Type Size Used Avail Use% Mounted on /dev/sda6 ext4 57G 2.7G 51G 6% / udev devtmpfs 1.9G 12K 1.9G 1% /dev tmpfs tmpfs 770M 892K 769M 1% /run none tmpfs 5.0M 0 5.0M 0% /run/lock none tmpfs 1.9G 260K 1.9G 1% /run/shm none tmpfs 100M 44K 100M 1% /run/user /dev/sda1 fuseblk 70G 36G 35G 51% /mnt/boot-sav/sda1 /dev/sda2 fuseblk 70G 66G 4.8G 94% /mnt/boot-sav/sda2 /dev/sda3 fuseblk 19G 87M 19G 1% /mnt/boot-sav/sda3 /dev/sda5 fuseblk 479G 436G 44G 92% /mnt/boot-sav/sda5 =================== fdisk -l: Disk /dev/sda: 750.2 GB, 750156374016 bytes 255 heads, 63 sectors/track, 91201 cylinders, total 1465149168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x1dc69d0b Device Boot Start End Blocks Id System /dev/sda1 * 206848 146802687 73297920 7 HPFS/NTFS/exFAT /dev/sda2 147007488 293623807 73308160 7 HPFS/NTFS/exFAT /dev/sda3 293623808 332820613 19598403 7 HPFS/NTFS/exFAT /dev/sda4 332822526 1465145343 566161409 f W95 Ext'd (LBA) Partition 4 does not start on physical sector boundary. /dev/sda5 461342720 1465145343 501901312 7 HPFS/NTFS/exFAT /dev/sda6 332822528 453171199 60174336 83 Linux /dev/sda7 453173248 461338623 4082688 82 Linux swap / Solaris Partition table entries are not in disk order =================== Recommended repair Recommended-Repair This setting will reinstall the grub2 of sda6 into the MBR of sda. Additional repair will be performed: unhide-bootmenu-10s grub-install (GRUB) 2.00-7ubuntu11,grub-install (GRUB) 2. Reinstall the GRUB of sda6 into the MBR of sda Installation finished. No error reported. grub-install /dev/sda: exit code of grub-install /dev/sda:0 update-grub Generating grub.cfg ... Found linux image: /boot/vmlinuz-3.5.0-17-generic Found initrd image: /boot/initrd.img-3.5.0-17-generic Found memtest86+ image: /boot/memtest86+.bin Found Windows 7 (loader) on /dev/sda1 Unhide GRUB boot menu in sda6/boot/grub/grub.cfg Boot successfully repaired. You can now reboot your computer. The boot files of [The OS now in use - Ubuntu 12.10] are far from the start of the disk. Your BIOS may not detect them. You may want to retry after creating a /boot partition (EXT4, >200MB, start of the disk). This can be performed via tools such as gParted. Then select this partition via the [Separate /boot partition:] option of [Boot Repair]. (https://help.ubuntu.com/community/BootPartition)

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Using BPEL Performance Statistics to Diagnose Performance Bottlenecks

- by fip

Tuning performance of Oracle SOA 11G applications could be challenging. Because SOA is a platform for you to build composite applications that connect many applications and "services", when the overall performance is slow, the bottlenecks could be anywhere in the system: the applications/services that SOA connects to, the infrastructure database, or the SOA server itself.How to quickly identify the bottleneck becomes crucial in tuning the overall performance. Fortunately, the BPEL engine in Oracle SOA 11G (and 10G, for that matter) collects BPEL Engine Performance Statistics, which show the latencies of low level BPEL engine activities. The BPEL engine performance statistics can make it a bit easier for you to identify the performance bottleneck. Although the BPEL engine performance statistics are always available, the access to and interpretation of them are somewhat obscure in the early and current (PS5) 11G versions. This blog attempts to offer instructions that help you to enable, retrieve and interpret the performance statistics, before the future versions provides a more pleasant user experience. Overview of BPEL Engine Performance Statistics SOA BPEL has a feature of collecting some performance statistics and store them in memory. One MBean attribute, StatLastN, configures the size of the memory buffer to store the statistics. This memory buffer is a "moving window", in a way that old statistics will be flushed out by the new if the amount of data exceeds the buffer size. Since the buffer size is limited by StatLastN, impacts of statistics collection on performance is minimal. By default StatLastN=-1, which means no collection of performance data. Once the statistics are collected in the memory buffer, they can be retrieved via another MBean oracle.as.soainfra.bpel:Location=[Server Name],name=BPELEngine,type=BPELEngine.> My friend in Oracle SOA development wrote this simple 'bpelstat' web app that looks up and retrieves the performance data from the MBean and displays it in a human readable form. It does not have beautiful UI but it is fairly useful. Although in Oracle SOA 11.1.1.5 onwards the same statistics can be viewed via a more elegant UI under "request break down" at EM -> SOA Infrastructure -> Service Engines -> BPEL -> Statistics, some unsophisticated minds like mine may still prefer the simplicity of the 'bpelstat' JSP. One thing that simple JSP does do well is that you can save the page and send it to someone to further analyze Follows are the instructions of how to install and invoke the BPEL statistic JSP. My friend in SOA Development will soon blog about interpreting the statistics. Stay tuned. Step1: Enable BPEL Engine Statistics for Each SOA Servers via Enterprise Manager First st you need to set the StatLastN to some number as a way to enable the collection of BPEL Engine Performance Statistics EM Console -> soa-infra(Server Name) -> SOA Infrastructure -> SOA Administration -> BPEL Properties Click on "More BPEL Configuration Properties" Click on attribute "StatLastN", set its value to some integer number. Typically you want to set it 1000 or more. Step 2: Download and Deploy bpelstat.war File to Admin Server, Note: the WAR file contains a JSP that does NOT have any security restriction. You do NOT want to keep in your production server for a long time as it is a security hazard. Deactivate the war once you are done. Download the bpelstat.war to your local PC At WebLogic Console, Go to Deployments -> Install Click on the "upload your file(s)" Click the "Browse" button to upload the deployment to Admin Server Accept the uploaded file as the path, click next Check the default option "Install this deployment as an application" Check "AdminServer" as the target server Finish the rest of the deployment with default settings Console -> Deployments Check the box next to "bpelstat" application Click on the "Start" button. It will change the state of the app from "prepared" to "active" Step 3: Invoke the BPEL Statistic Tool The BPELStat tool merely call the MBean of BPEL server and collects and display the in-memory performance statics. You usually want to do that after some peak loads. Go to http://<admin-server-host>:<admin-server-port>/bpelstat Enter the correct admin hostname, port, username and password Enter the SOA Server Name from which you want to collect the performance statistics. For example, SOA_MS1, etc. Click Submit Keep doing the same for all SOA servers. Step 3: Interpret the BPEL Engine Statistics You will see a few categories of BPEL Statistics from the JSP Page. First it starts with the overall latency of BPEL processes, grouped by synchronous and asynchronous processes. Then it provides the further break down of the measurements through the life time of a BPEL request, which is called the "request break down". 1. Overall latency of BPEL processes The top of the page shows that the elapse time of executing the synchronous process TestSyncBPELProcess from the composite TestComposite averages at about 1543.21ms, while the elapse time of executing the asynchronous process TestAsyncBPELProcess from the composite TestComposite2 averages at about 1765.43ms. The maximum and minimum latency were also shown. Synchronous process statistics <statistics> <stats key="default/TestComposite!2.0.2-ScopedJMSOSB*soa_bfba2527-a9ba-41a7-95c5-87e49c32f4ff/TestSyncBPELProcess" min="1234" max="4567" average="1543.21" count="1000"> </stats> </statistics> Asynchronous process statistics <statistics> <stats key="default/TestComposite2!2.0.2-ScopedJMSOSB*soa_bfba2527-a9ba-41a7-95c5-87e49c32f4ff/TestAsyncBPELProcess" min="2234" max="3234" average="1765.43" count="1000"> </stats> </statistics> 2. Request break down Under the overall latency categorized by synchronous and asynchronous processes is the "Request breakdown". Organized by statistic keys, the Request breakdown gives finer grain performance statistics through the life time of the BPEL requests.It uses indention to show the hierarchy of the statistics. Request breakdown <statistics> <stats key="eng-composite-request" min="0" max="0" average="0.0" count="0"> <stats key="eng-single-request" min="22" max="606" average="258.43" count="277"> <stats key="populate-context" min="0" max="0" average="0.0" count="248"> Please note that in SOA 11.1.1.6, the statistics under Request breakdown is aggregated together cross all the BPEL processes based on statistic keys. It does not differentiate between BPEL processes. If two BPEL processes happen to have the statistic that share same statistic key, the statistics from two BPEL processes will be aggregated together. Keep this in mind when we go through more details below. 2.1 BPEL process activity latencies A very useful measurement in the Request Breakdown is the performance statistics of the BPEL activities you put in your BPEL processes: Assign, Invoke, Receive, etc. The names of the measurement in the JSP page directly come from the names to assign to each BPEL activity. These measurements are under the statistic key "actual-perform" Example 1: Follows is the measurement for BPEL activity "AssignInvokeCreditProvider_Input", which looks like the Assign activity in a BPEL process that assign an input variable before passing it to the invocation: <stats key="AssignInvokeCreditProvider_Input" min="1" max="8" average="1.9" count="153"> <stats key="sensor-send-activity-data" min="0" max="1" average="0.0" count="306"> </stats> <stats key="sensor-send-variable-data" min="0" max="0" average="0.0" count="153"> </stats> <stats key="monitor-send-activity-data" min="0" max="0" average="0.0" count="306"> </stats> </stats> Note: because as previously mentioned that the statistics cross all BPEL processes are aggregated together based on statistic keys, if two BPEL processes happen to name their Invoke activity the same name, they will show up at one measurement (i.e. statistic key). Example 2: Follows is the measurement of BPEL activity called "InvokeCreditProvider". You can not only see that by average it takes 3.31ms to finish this call (pretty fast) but also you can see from the further break down that most of this 3.31 ms was spent on the "invoke-service". <stats key="InvokeCreditProvider" min="1" max="13" average="3.31" count="153"> <stats key="initiate-correlation-set-again" min="0" max="0" average="0.0" count="153"> </stats> <stats key="invoke-service" min="1" max="13" average="3.08" count="153"> <stats key="prep-call" min="0" max="1" average="0.04" count="153"> </stats> </stats> <stats key="initiate-correlation-set" min="0" max="0" average="0.0" count="153"> </stats> <stats key="sensor-send-activity-data" min="0" max="0" average="0.0" count="306"> </stats> <stats key="sensor-send-variable-data" min="0" max="0" average="0.0" count="153"> </stats> <stats key="monitor-send-activity-data" min="0" max="0" average="0.0" count="306"> </stats> <stats key="update-audit-trail" min="0" max="2" average="0.03" count="153"> </stats> </stats> 2.2 BPEL engine activity latency Another type of measurements under Request breakdown are the latencies of underlying system level engine activities. These activities are not directly tied to a particular BPEL process or process activity, but they are critical factors in the overall engine performance. These activities include the latency of saving asynchronous requests to database, and latency of process dehydration. My friend Malkit Bhasin is working on providing more information on interpreting the statistics on engine activities on his blog (https://blogs.oracle.com/malkit/). I will update this blog once the information becomes available. Update on 2012-10-02: My friend Malkit Bhasin has published the detail interpretation of the BPEL service engine statistics at his blog http://malkit.blogspot.com/2012/09/oracle-bpel-engine-soa-suite.html.

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Table sorting & pagination with jQuery and Razor in ASP.NET MVC

- by hajan

Introduction jQuery enjoys living inside pages which are built on top of ASP.NET MVC Framework. The ASP.NET MVC is a place where things are organized very well and it is quite hard to make them dirty, especially because the pattern enforces you on purity (you can still make it dirty if you want so ;) ). We all know how easy is to build a HTML table with a header row, footer row and table rows showing some data. With ASP.NET MVC we can do this pretty easy, but, the result will be pure HTML table which only shows data, but does not includes sorting, pagination or some other advanced features that we were used to have in the ASP.NET WebForms GridView. Ok, there is the WebGrid MVC Helper, but what if we want to make something from pure table in our own clean style? In one of my recent projects, I’ve been using the jQuery tablesorter and tablesorter.pager plugins that go along. You don’t need to know jQuery to make this work… You need to know little CSS to create nice design for your table, but of course you can use mine from the demo… So, what you will see in this blog is how to attach this plugin to your pure html table and a div for pagination and make your table with advanced sorting and pagination features. Demo Project Resources The resources I’m using for this demo project are shown in the following solution explorer window print screen: Content/images – folder that contains all the up/down arrow images, pagination buttons etc. You can freely replace them with your own, but keep the names the same if you don’t want to change anything in the CSS we will built later. Content/Site.css – The main css theme, where we will add the theme for our table too Controllers/HomeController.cs – The controller I’m using for this project Models/Person.cs – For this demo, I’m using Person.cs class Scripts – jquery-1.4.4.min.js, jquery.tablesorter.js, jquery.tablesorter.pager.js – required script to make the magic happens Views/Home/Index.cshtml – Index view (razor view engine) the other items are not important for the demo. ASP.NET MVC 1. Model In this demo I use only one Person class which defines Person entity with several properties. You can use your own model, maybe one which will access data from database or any other resource. Person.cs public class Person { public string Name { get; set; } public string Surname { get; set; } public string Email { get; set; } public int? Phone { get; set; } public DateTime? DateAdded { get; set; } public int? Age { get; set; } public Person(string name, string surname, string email, int? phone, DateTime? dateadded, int? age) { Name = name; Surname = surname; Email = email; Phone = phone; DateAdded = dateadded; Age = age; } } 2. View In our example, we have only one Index.chtml page where Razor View engine is used. Razor view engine is my favorite for ASP.NET MVC because it’s very intuitive, fluid and keeps your code clean. 3. Controller Since this is simple example with one page, we use one HomeController.cs where we have two methods, one of ActionResult type (Index) and another GetPeople() used to create and return list of people. HomeController.cs public class HomeController : Controller { // // GET: /Home/ public ActionResult Index() { ViewBag.People = GetPeople(); return View(); } public List<Person> GetPeople() { List<Person> listPeople = new List<Person>(); listPeople.Add(new Person("Hajan", "Selmani", "[email protected]", 070070070,DateTime.Now, 25)); listPeople.Add(new Person("Straight", "Dean", "[email protected]", 123456789, DateTime.Now.AddDays(-5), 35)); listPeople.Add(new Person("Karsen", "Livia", "[email protected]", 46874651, DateTime.Now.AddDays(-2), 31)); listPeople.Add(new Person("Ringer", "Anne", "[email protected]", null, DateTime.Now, null)); listPeople.Add(new Person("O'Leary", "Michael", "[email protected]", 32424344, DateTime.Now, 44)); listPeople.Add(new Person("Gringlesby", "Anne", "[email protected]", null, DateTime.Now.AddDays(-9), 18)); listPeople.Add(new Person("Locksley", "Stearns", "[email protected]", 2135345, DateTime.Now, null)); listPeople.Add(new Person("DeFrance", "Michel", "[email protected]", 235325352, DateTime.Now.AddDays(-18), null)); listPeople.Add(new Person("White", "Johnson", null, null, DateTime.Now.AddDays(-22), 55)); listPeople.Add(new Person("Panteley", "Sylvia", null, 23233223, DateTime.Now.AddDays(-1), 32)); listPeople.Add(new Person("Blotchet-Halls", "Reginald", null, 323243423, DateTime.Now, 26)); listPeople.Add(new Person("Merr", "South", "[email protected]", 3232442, DateTime.Now.AddDays(-5), 85)); listPeople.Add(new Person("MacFeather", "Stearns", "[email protected]", null, DateTime.Now, null)); return listPeople; } } TABLE CSS/HTML DESIGN Now, lets start with the implementation. First of all, lets create the table structure and the main CSS. 1. HTML Structure @{ Layout = null; } <!DOCTYPE html> <html> <head> <title>ASP.NET & jQuery</title>  </head> <body> <div> <table class="tablesorter"> <thead> <tr> <th> value </th> </tr> </thead> <tbody> <tr> <td>value</td> </tr> </tbody> <tfoot> <tr> <th> value </th> </tr> </tfoot> </table> <div id="pager"> </div> </div> </body> </html> So, this is the main structure you need to create for each of your tables where you want to apply the functionality we will create. Of course the scripts are referenced once ;). As you see, our table has class tablesorter and also we have a div with id pager. In the next steps we will use both these to create the needed functionalities. The complete Index.cshtml coded to get the data from controller and display in the page is: <body> <div> <table class="tablesorter"> <thead> <tr> <th>Name</th> <th>Surname</th> <th>Email</th> <th>Phone</th> <th>Date Added</th> </tr> </thead> <tbody> @{ foreach (var p in ViewBag.People) { <tr> <td>@p.Name</td> <td>@p.Surname</td> <td>@p.Email</td> <td>@p.Phone</td> <td>@p.DateAdded</td> </tr> } } </tbody> <tfoot> <tr> <th>Name</th> <th>Surname</th> <th>Email</th> <th>Phone</th> <th>Date Added</th> </tr> </tfoot> </table> <div id="pager" style="position: none;"> <form> <img src="@Url.Content("~/Content/images/first.png")" class="first" /> <img src="@Url.Content("~/Content/images/prev.png")" class="prev" /> <input type="text" class="pagedisplay" /> <img src="@Url.Content("~/Content/images/next.png")" class="next" /> <img src="@Url.Content("~/Content/images/last.png")" class="last" /> <select class="pagesize"> <option selected="selected" value="5">5</option> <option value="10">10</option> <option value="20">20</option> <option value="30">30</option> <option value="40">40</option> </select> </form> </div> </div> </body> So, mainly the structure is the same. I have added @Razor code to create table with data retrieved from the ViewBag.People which has been filled with data in the home controller. 2. CSS Design The CSS code I’ve created is: /* DEMO TABLE */ body { font-size: 75%; font-family: Verdana, Tahoma, Arial, "Helvetica Neue", Helvetica, Sans-Serif; color: #232323; background-color: #fff; } table { border-spacing:0; border:1px solid gray;} table.tablesorter thead tr .header { background-image: url(images/bg.png); background-repeat: no-repeat; background-position: center right; cursor: pointer; } table.tablesorter tbody td { color: #3D3D3D; padding: 4px; background-color: #FFF; vertical-align: top; } table.tablesorter tbody tr.odd td { background-color:#F0F0F6; } table.tablesorter thead tr .headerSortUp { background-image: url(images/asc.png); } table.tablesorter thead tr .headerSortDown { background-image: url(images/desc.png); } table th { width:150px; border:1px outset gray; background-color:#3C78B5; color:White; cursor:pointer; } table thead th:hover { background-color:Yellow; color:Black;} table td { width:150px; border:1px solid gray;} PAGINATION AND SORTING Now, when everything is ready and we have the data, lets make pagination and sorting functionalities 1. jQuery Scripts referencing <link href="@Url.Content("~/Content/Site.css")" rel="stylesheet" type="text/css" /> <script src="@Url.Content("~/Scripts/jquery-1.4.4.min.js")" type="text/javascript"></script> <script src="@Url.Content("~/Scripts/jquery.tablesorter.js")" type="text/javascript"></script> <script src="@Url.Content("~/Scripts/jquery.tablesorter.pager.js")" type="text/javascript"></script> 2. jQuery Sorting and Pagination script <script type="text/javascript"> $(function () { $("table.tablesorter").tablesorter({ widthFixed: true, sortList: [[0, 0]] }) .tablesorterPager({ container: $("#pager"), size: $(".pagesize option:selected").val() }); }); </script> So, with only two lines of code, I’m using both tablesorter and tablesorterPager plugins, giving some options to both these. Options added: tablesorter - widthFixed: true – gives fixed width of the columns tablesorter - sortList[[0,0]] – An array of instructions for per-column sorting and direction in the format: [[columnIndex, sortDirection], ... ] where columnIndex is a zero-based index for your columns left-to-right and sortDirection is 0 for Ascending and 1 for Descending. A valid argument that sorts ascending first by column 1 and then column 2 looks like: [[0,0],[1,0]] (source: http://tablesorter.com/docs/) tablesorterPager – container: $(“#pager”) – tells the pager container, the div with id pager in our case. tablesorterPager – size: the default size of each page, where I get the default value selected, so if you put selected to any other of the options in your select list, you will have this number of rows as default per page for the table too. END RESULTS 1. Table once the page is loaded (default results per page is 5 and is automatically sorted by 1st column as sortList is specified) 2. Sorted by Phone Descending 3. Changed pagination to 10 items per page 4. Sorted by Phone and Name (use SHIFT to sort on multiple columns) 5. Sorted by Date Added 6. Page 3, 5 items per page ADDITIONAL ENHANCEMENTS We can do additional enhancements to the table. We can make search for each column. I will cover this in one of my next blogs. Stay tuned. DEMO PROJECT You can download demo project source code from HERE.CONCLUSION Once you finish with the demo, run your page and open the source code. You will be amazed of the purity of your code.Working with pagination in client side can be very useful. One of the benefits is performance, but if you have thousands of rows in your tables, you will get opposite result when talking about performance. Hence, sometimes it is nice idea to make pagination on back-end. So, the compromise between both approaches would be best to combine both of them. I use at most up to 500 rows on client-side and once the user reach the last page, we can trigger ajax postback which can get the next 500 rows using server-side pagination of the same data. I would like to recommend the following blog post http://weblogs.asp.net/gunnarpeipman/archive/2010/09/14/returning-paged-results-from-repositories-using-pagedresult-lt-t-gt.aspx, which will help you understand how to return page results from repository. I hope this was helpful post for you. Wait for my next posts ;). Please do let me know your feedback. Best Regards, Hajan

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Developing web apps using ASP.NET MVC 3, Razor and EF Code First - Part 1

- by shiju

In this post, I will demonstrate web application development using ASP. NET MVC 3, Razor and EF code First. This post will also cover Dependency Injection using Unity 2.0 and generic Repository and Unit of Work for EF Code First. The following frameworks will be used for this step by step tutorial. ASP.NET MVC 3 EF Code First CTP 5 Unity 2.0 Define Domain Model Let’s create domain model for our simple web application Category class public class Category { public int CategoryId { get; set; } [Required(ErrorMessage = "Name Required")] [StringLength(25, ErrorMessage = "Must be less than 25 characters")] public string Name { get; set;} public string Description { get; set; } public virtual ICollection<Expense> Expenses { get; set; } } Expense class public class Expense { public int ExpenseId { get; set; } public string Transaction { get; set; } public DateTime Date { get; set; } public double Amount { get; set; } public int CategoryId { get; set; } public virtual Category Category { get; set; } } We have two domain entities - Category and Expense. A single category contains a list of expense transactions and every expense transaction should have a Category. In this post, we will be focusing on CRUD operations for the entity Category and will be working on the Expense entity with a View Model object in the later post. And the source code for this application will be refactored over time. The above entities are very simple POCO (Plain Old CLR Object) classes and the entity Category is decorated with validation attributes in the System.ComponentModel.DataAnnotations namespace. Now we want to use these entities for defining model objects for the Entity Framework 4. Using the Code First approach of Entity Framework, we can first define the entities by simply writing POCO classes without any coupling with any API or database library. This approach lets you focus on domain model which will enable Domain-Driven Development for applications. EF code first support is currently enabled with a separate API that is runs on top of the Entity Framework 4. EF Code First is reached CTP 5 when I am writing this article. Creating Context Class for Entity Framework We have created our domain model and let’s create a class in order to working with Entity Framework Code First. For this, you have to download EF Code First CTP 5 and add reference to the assembly EntitFramework.dll. You can also use NuGet to download add reference to EEF Code First. public class MyFinanceContext : DbContext { public MyFinanceContext() : base("MyFinance") { } public DbSet<Category> Categories { get; set; } public DbSet<Expense> Expenses { get; set; } } The above class MyFinanceContext is derived from DbContext that can connect your model classes to a database. The MyFinanceContext class is mapping our Category and Expense class into database tables Categories and Expenses using DbSet<TEntity> where TEntity is any POCO class. When we are running the application at first time, it will automatically create the database. EF code-first look for a connection string in web.config or app.config that has the same name as the dbcontext class. If it is not find any connection string with the convention, it will automatically create database in local SQL Express database by default and the name of the database will be same name as the dbcontext class. You can also define the name of database in constructor of the the dbcontext class. Unlike NHibernate, we don’t have to use any XML based mapping files or Fluent interface for mapping between our model and database. The model classes of Code First are working on the basis of conventions and we can also use a fluent API to refine our model. The convention for primary key is ‘Id’ or ‘<class name>Id’. If primary key properties are detected with type ‘int’, ‘long’ or ‘short’, they will automatically registered as identity columns in the database by default. Primary key detection is not case sensitive. We can define our model classes with validation attributes in the System.ComponentModel.DataAnnotations namespace and it automatically enforces validation rules when a model object is updated or saved. Generic Repository for EF Code First We have created model classes and dbcontext class. Now we have to create generic repository pattern for data persistence with EF code first. If you don’t know about the repository pattern, checkout Martin Fowler’s article on Repository Let’s create a generic repository to working with DbContext and DbSet generics. public interface IRepository<T> where T : class { void Add(T entity); void Delete(T entity); T GetById(long Id); IEnumerable<T> All(); } RepositoryBasse – Generic Repository class public abstract class RepositoryBase<T> where T : class { private MyFinanceContext database; private readonly IDbSet<T> dbset; protected RepositoryBase(IDatabaseFactory databaseFactory) { DatabaseFactory = databaseFactory; dbset = Database.Set<T>(); } protected IDatabaseFactory DatabaseFactory { get; private set; } protected MyFinanceContext Database { get { return database ?? (database = DatabaseFactory.Get()); } } public virtual void Add(T entity) { dbset.Add(entity); } public virtual void Delete(T entity) { dbset.Remove(entity); } public virtual T GetById(long id) { return dbset.Find(id); } public virtual IEnumerable<T> All() { return dbset.ToList(); } } DatabaseFactory class public class DatabaseFactory : Disposable, IDatabaseFactory { private MyFinanceContext database; public MyFinanceContext Get() { return database ?? (database = new MyFinanceContext()); } protected override void DisposeCore() { if (database != null) database.Dispose(); } } Unit of Work If you are new to Unit of Work pattern, checkout Fowler’s article on Unit of Work . According to Martin Fowler, the Unit of Work pattern "maintains a list of objects affected by a business transaction and coordinates the writing out of changes and the resolution of concurrency problems." Let’s create a class for handling Unit of Work public interface IUnitOfWork { void Commit(); } UniOfWork class public class UnitOfWork : IUnitOfWork { private readonly IDatabaseFactory databaseFactory; private MyFinanceContext dataContext; public UnitOfWork(IDatabaseFactory databaseFactory) { this.databaseFactory = databaseFactory; } protected MyFinanceContext DataContext { get { return dataContext ?? (dataContext = databaseFactory.Get()); } } public void Commit() { DataContext.Commit(); } } The Commit method of the UnitOfWork will call the commit method of MyFinanceContext class and it will execute the SaveChanges method of DbContext class. Repository class for Category In this post, we will be focusing on the persistence against Category entity and will working on other entities in later post. Let’s create a repository for handling CRUD operations for Category using derive from a generic Repository RepositoryBase<T>. public class CategoryRepository: RepositoryBase<Category>, ICategoryRepository { public CategoryRepository(IDatabaseFactory databaseFactory) : base(databaseFactory) { } } public interface ICategoryRepository : IRepository<Category> { } If we need additional methods than generic repository for the Category, we can define in the CategoryRepository. Dependency Injection using Unity 2.0 If you are new to Inversion of Control/ Dependency Injection or Unity, please have a look on my articles at http://weblogs.asp.net/shijuvarghese/archive/tags/IoC/default.aspx. I want to create a custom lifetime manager for Unity to store container in the current HttpContext. public class HttpContextLifetimeManager<T> : LifetimeManager, IDisposable { public override object GetValue() { return HttpContext.Current.Items[typeof(T).AssemblyQualifiedName]; } public override void RemoveValue() { HttpContext.Current.Items.Remove(typeof(T).AssemblyQualifiedName); } public override void SetValue(object newValue) { HttpContext.Current.Items[typeof(T).AssemblyQualifiedName] = newValue; } public void Dispose() { RemoveValue(); } } Let’s create controller factory for Unity in the ASP.NET MVC 3 application. public class UnityControllerFactory : DefaultControllerFactory { IUnityContainer container; public UnityControllerFactory(IUnityContainer container) { this.container = container; } protected override IController GetControllerInstance(RequestContext reqContext, Type controllerType) { IController controller; if (controllerType == null) throw new HttpException( 404, String.Format( "The controller for path '{0}' could not be found" + "or it does not implement IController.", reqContext.HttpContext.Request.Path)); if (!typeof(IController).IsAssignableFrom(controllerType)) throw new ArgumentException( string.Format( "Type requested is not a controller: {0}", controllerType.Name), "controllerType"); try { controller= container.Resolve(controllerType) as IController; } catch (Exception ex) { throw new InvalidOperationException(String.Format( "Error resolving controller {0}", controllerType.Name), ex); } return controller; } } Configure contract and concrete types in Unity Let’s configure our contract and concrete types in Unity for resolving our dependencies. private void ConfigureUnity() { //Create UnityContainer IUnityContainer container = new UnityContainer() .RegisterType<IDatabaseFactory, DatabaseFactory>(new HttpContextLifetimeManager<IDatabaseFactory>()) .RegisterType<IUnitOfWork, UnitOfWork>(new HttpContextLifetimeManager<IUnitOfWork>()) .RegisterType<ICategoryRepository, CategoryRepository>(new HttpContextLifetimeManager<ICategoryRepository>()); //Set container for Controller Factory ControllerBuilder.Current.SetControllerFactory( new UnityControllerFactory(container)); } In the above ConfigureUnity method, we are registering our types onto Unity container with custom lifetime manager HttpContextLifetimeManager. Let’s call ConfigureUnity method in the Global.asax.cs for set controller factory for Unity and configuring the types with Unity. protected void Application_Start() { AreaRegistration.RegisterAllAreas(); RegisterGlobalFilters(GlobalFilters.Filters); RegisterRoutes(RouteTable.Routes); ConfigureUnity(); } Developing web application using ASP.NET MVC 3 We have created our domain model for our web application and also have created repositories and configured dependencies with Unity container. Now we have to create controller classes and views for doing CRUD operations against the Category entity. Let’s create controller class for Category Category Controller public class CategoryController : Controller { private readonly ICategoryRepository categoryRepository; private readonly IUnitOfWork unitOfWork; public CategoryController(ICategoryRepository categoryRepository, IUnitOfWork unitOfWork) { this.categoryRepository = categoryRepository; this.unitOfWork = unitOfWork; } public ActionResult Index() { var categories = categoryRepository.All(); return View(categories); } [HttpGet] public ActionResult Edit(int id) { var category = categoryRepository.GetById(id); return View(category); } [HttpPost] public ActionResult Edit(int id, FormCollection collection) { var category = categoryRepository.GetById(id); if (TryUpdateModel(category)) { unitOfWork.Commit(); return RedirectToAction("Index"); } else return View(category); } [HttpGet] public ActionResult Create() { var category = new Category(); return View(category); } [HttpPost] public ActionResult Create(Category category) { if (!ModelState.IsValid) { return View("Create", category); } categoryRepository.Add(category); unitOfWork.Commit(); return RedirectToAction("Index"); } [HttpPost] public ActionResult Delete(int id) { var category = categoryRepository.GetById(id); categoryRepository.Delete(category); unitOfWork.Commit(); var categories = categoryRepository.All(); return PartialView("CategoryList", categories); } } Creating Views in Razor Now we are going to create views in Razor for our ASP.NET MVC 3 application. Let’s create a partial view CategoryList.cshtml for listing category information and providing link for Edit and Delete operations. CategoryList.cshtml @using MyFinance.Helpers; @using MyFinance.Domain; @model IEnumerable<Category> <table> <tr> <th>Actions</th> <th>Name</th> <th>Description</th> </tr> @foreach (var item in Model) { <tr> <td> @Html.ActionLink("Edit", "Edit",new { id = item.CategoryId }) @Ajax.ActionLink("Delete", "Delete", new { id = item.CategoryId }, new AjaxOptions { Confirm = "Delete Expense?", HttpMethod = "Post", UpdateTargetId = "divCategoryList" }) </td> <td> @item.Name </td> <td> @item.Description </td> </tr> } </table> <p> @Html.ActionLink("Create New", "Create") </p> The delete link is providing Ajax functionality using the Ajax.ActionLink. This will call an Ajax request for Delete action method in the CategoryCotroller class. In the Delete action method, it will return Partial View CategoryList after deleting the record. We are using CategoryList view for the Ajax functionality and also for Index view using for displaying list of category information. Let’s create Index view using partial view CategoryList Index.chtml @model IEnumerable<MyFinance.Domain.Category> @{ ViewBag.Title = "Index"; } <h2>Category List</h2> <script src="@Url.Content("~/Scripts/jquery.unobtrusive-ajax.min.js")" type="text/javascript"></script> <div id="divCategoryList"> @Html.Partial("CategoryList", Model) </div> We can call the partial views using Html.Partial helper method. Now we are going to create View pages for insert and update functionality for the Category. Both view pages are sharing common user interface for entering the category information. So I want to create an EditorTemplate for the Category information. We have to create the EditorTemplate with the same name of entity object so that we can refer it on view pages using @Html.EditorFor(model => model) . So let’s create template with name Category. Let’s create view page for insert Category information @model MyFinance.Domain.Category @{ ViewBag.Title = "Save"; } <h2>Create</h2> <script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script> <script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script> @using (Html.BeginForm()) { @Html.ValidationSummary(true) <fieldset> <legend>Category</legend> @Html.EditorFor(model => model) <p> <input type="submit" value="Create" /> </p> </fieldset> } <div> @Html.ActionLink("Back to List", "Index") </div> ViewStart file In Razor views, we can add a file named _viewstart.cshtml in the views directory and this will be shared among the all views with in the Views directory. The below code in the _viewstart.cshtml, sets the Layout page for every Views in the Views folder. @{ Layout = "~/Views/Shared/_Layout.cshtml"; } Source Code You can download the source code from http://efmvc.codeplex.com/ . The source will be refactored on over time. Summary In this post, we have created a simple web application using ASP.NET MVC 3 and EF Code First. We have discussed on technologies and practices such as ASP.NET MVC 3, Razor, EF Code First, Unity 2, generic Repository and Unit of Work. In my later posts, I will modify the application and will be discussed on more things. Stay tuned to my blog for more posts on step by step application building.

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Red Gate Coder interviews: Robin Hellen

- by Michael Williamson

Robin Hellen is a test engineer here at Red Gate, and is also the latest coder I’ve interviewed. We chatted about debugging code, the roles of software engineers and testers, and why Vala is currently his favourite programming language. How did you get started with programming?It started when I was about six. My dad’s a professional programmer, and he gave me and my sister one of his old computers and taught us a bit about programming. It was an old Amiga 500 with a variant of BASIC. I don’t think I ever successfully completed anything! It was just faffing around. I didn’t really get anywhere with it.But then presumably you did get somewhere with it at some point.At some point. The PC emerged as the dominant platform, and I learnt a bit of Visual Basic. I didn’t really do much, just a couple of quick hacky things. A bit of demo animation. Took me a long time to get anywhere with programming, really.When did you feel like you did start to get somewhere?I think it was when I started doing things for someone else, which was my sister’s final year of university project. She called up my dad two days before she was due to submit, saying “We need something to display a graph!”. Dad says, “I’m too busy, go talk to your brother”. So I hacked up this ugly piece of code, sent it off and they won a prize for that project. Apparently, the graph, the bit that I wrote, was the reason they won a prize! That was when I first felt that I’d actually done something that was worthwhile. That was my first real bit of code, and the ugliest code I’ve ever written. It’s basically an array of pre-drawn line elements that I shifted round the screen to draw a very spikey graph.When did you decide that programming might actually be something that you wanted to do as a career?It’s not really a decision I took, I always wanted to do something with computers. And I had to take a gap year for uni, so I was looking for twelve month internships. I applied to Red Gate, and they gave me a job as a tester. And that’s where I really started having to write code well. To a better standard that I had been up to that point.How did you find coming to Red Gate and working with other coders?I thought it was really nice. I learnt so much just from other people around. I think one of the things that’s really great is that people are just willing to help you learn. Instead of “Don’t you know that, you’re so stupid”, it’s “You can just do it this way”.If you could go back to the very start of that internship, is there something that you would tell yourself?Write shorter code. I have a tendency to write massive, many-thousand line files that I break out of right at the end. And then half-way through a project I’m doing something, I think “Where did I write that bit that does that thing?”, and it’s almost impossible to find. I wrote some horrendous code when I started. Just that principle, just keep things short. Even if looks a bit crazy to be jumping around all over the place all of the time, it’s actually a lot more understandable.And how do you hold yourself to that?Generally, if a function’s going off my screen, it’s probably too long. That’s what I tell myself, and within the team here we have code reviews, so the guys I’m with at the moment are pretty good at pulling me up on, “Doesn’t that look like it’s getting a bit long?”. It’s more just the subjective standard of readability than anything.So you’re an advocate of code review?Yes, definitely. Both to spot errors that you might have made, and to improve your knowledge. The person you’re reviewing will say “Oh, you could have done it that way”. That’s how we learn, by talking to others, and also just sharing knowledge of how your project works around the team, or even outside the team. Definitely a very firm advocate of code reviews.Do you think there’s more we could do with them?I don’t know. We’re struggling with how to add them as part of the process without it becoming too cumbersome. We’ve experimented with a few different ways, and we’ve not found anything that just works.To get more into the nitty gritty: how do you like to debug code?The first thing is to do it in my head. I’ll actually think what piece of code is likely to have caused that error, and take a quick look at it, just to see if there’s anything glaringly obvious there. The next thing I’ll probably do is throw in print statements, or throw some exceptions from various points, just to check: is it going through the code path I expect it to? A last resort is to actually debug code using a debugger.Why is the debugger the last resort?Probably because of the environments I learnt programming in. VB and early BASIC didn’t have much of a debugger, the only way to find out what your program was doing was to add print statements. Also, because a lot of the stuff I tend to work with is non-interactive, if it’s something that takes a long time to run, I can throw in the print statements, set a run off, go and do something else, and look at it again later, rather than trying to remember what happened at that point when I was debugging through it. So it also gives me the record of what happens. I hate just sitting there pressing F5, F5, continually. If you’re having to find out what your code is doing at each line, you’ve probably got a very wrong mental model of what your code’s doing, and you can find that out just as easily by inspecting a couple of values through the print statements.If I were on some codebase that you were also working on, what should I do to make it as easy as possible to understand?I’d say short and well-named methods. The one thing I like to do when I’m looking at code is to find out where a value comes from, and the more layers of indirection there are, particularly DI [dependency injection] frameworks, the harder it is to find out where something’s come from. I really hate that. I want to know if the value come from the user here or is a constant here, and if I can’t find that out, that makes code very hard to understand for me.As a tester, where do you think the split should lie between software engineers and testers?I think the split is less on areas of the code you write and more what you’re designing and creating. The developers put a structure on the code, while my major role is to say which tests we should have, whether we should test that, or it’s not worth testing that because it’s a tiny function in code that nobody’s ever actually going to see. So it’s not a split in the code, it’s a split in what you’re thinking about. Saying what code we should write, but alternatively what code we should take out.In your experience, do the software engineers tend to do much testing themselves?They tend to control the lowest layer of tests. And, depending on how the balance of people is in the team, they might write some of the higher levels of test. Or that might go to the testers. I’m the only tester on my team with three other developers, so they’ll be writing quite a lot of the actual test code, with input from me as to whether we should test that functionality, whereas on other teams, where it’s been more equal numbers, the testers have written pretty much all of the high level tests, just because that’s the best use of resource.If you could shuffle resources around however you liked, do you think that the developers should be writing those high-level tests?I think they should be writing them occasionally. It helps when they have an understanding of how testing code works and possibly what assumptions we’ve made in tests, and they can say “actually, it doesn’t work like that under the hood so you’ve missed this whole area”. It’s one of those agile things that everyone on the team should be at least comfortable doing the various jobs. So if the developers can write test code then I think that’s a very good thing.So you think testers should be able to write production code?Yes, although given most testers skills at coding, I wouldn’t advise it too much! I have written a few things, and I did make a few changes that have actually gone into our production code base. They’re not necessarily running every time but they are there. I think having that mix of skill sets is really useful. In some ways we’re using our own product to test itself, so being able to make those changes where it’s not working saves me a round-trip through the developers. It can be really annoying if the developers have no time to make a change, and I can’t touch the code.If the software engineers are consistently writing tests at all levels, what role do you think the role of a tester is?I think on a team like that, those distinctions aren’t quite so useful. There’ll be two cases. There’s either the case where the developers think they’ve written good tests, but you still need someone with a test engineer mind-set to go through the tests and validate that it’s a useful set, or the correct set for that code. Or they won’t actually be pure developers, they’ll have that mix of test ability in there.I think having slightly more distinct roles is useful. When it starts to blur, then you lose that view of the tests as a whole. The tester job is not to create tests, it’s to validate the quality of the product, and you don’t do that just by writing tests. There’s more things you’ve got to keep in your mind. And I think when you blur the roles, you start to lose that end of the tester.So because you’re working on those features, you lose that holistic view of the whole system?Yeah, and anyone who’s worked on the feature shouldn’t be testing it. You always need to have it tested it by someone who didn’t write it. Otherwise you’re a bit too close and you assume “yes, people will only use it that way”, but the tester will come along and go “how do people use this? How would our most idiotic user use this?”. I might not test that because it might be completely irrelevant. But it’s coming in and trying to have a different set of assumptions.Are you a believer that it should all be automated if possible?Not entirely. So an automated test is always better than a manual test for the long-term, but there’s still nothing that beats a human sitting in front of the application and thinking “What could I do at this point?”. The automated test is very good but they follow that strict path, and they never check anything off the path. The human tester will look at things that they weren’t expecting, whereas the automated test can only ever go “Is that value correct?” in many respects, and it won’t notice that on the other side of the screen you’re showing something completely wrong. And that value might have been checked independently, but you always find a few odd interactions when you’re going through something manually, and you always need to go through something manually to start with anyway, otherwise you won’t know where the important bits to write your automation are.When you’re doing that manual testing, do you think it’s important to do that across the entire product, or just the bits that you’ve touched recently?I think it’s important to do it mostly on the bits you’ve touched, but you can’t ignore the rest of the product. Unless you’re dealing with a very, very self-contained bit, you’re almost always encounter other bits of the product along the way. Most testers I know, even if they are looking at just one path, they’ll keep open and move around a bit anyway, just because they want to find something that’s broken. If we find that your path is right, we’ll go out and hunt something else.How do you think this fits into the idea of continuously deploying, so long as the tests pass?With deploying a website it’s a bit different because you can always pull it back. If you’re deploying an application to customers, when you’ve released it, it’s out there, you can’t pull it back. Someone’s going to keep it, no matter how hard you try there will be a few installations that stay around. So I’d always have at least a human element on that path. With websites, you could probably automate straight out, or at least straight out to an internal environment or a single server in a cloud of fifty that will serve some people. But I don’t think you should release to everyone just on automated tests passing.You’ve already mentioned using BASIC and C# — are there any other languages that you’ve used?I’ve used a few. That’s something that has changed more recently, I’ve become familiar with more languages. Before I started at Red Gate I learnt a bit of C. Then last year, I taught myself Python which I actually really enjoyed using. I’ve also come across another language called Vala, which is sort of a C#-like language. It’s basically a pre-processor for C, but it has very nice syntax. I think that’s currently my favourite language.Any particular reason for trying Vala?I have a completely Linux environment at home, and I’ve been looking for a nice language, and C# just doesn’t cut it because I won’t touch Mono. So, I was looking for something like C# but that was useable in an open source environment, and Vala’s what I found. C#’s got a few features that Vala doesn’t, and Vala’s got a few features where I think “It would be awesome if C# had that”.What are some of the features that it’s missing?Extension methods. And I think that’s the only one that really bugs me. I like to use them when I’m writing C# because it makes some things really easy, especially with libraries that you can’t touch the internals of. It doesn’t have method overloading, which is sometimes annoying.Where it does win over C#?Everything is non-nullable by default, you never have to check that something’s unexpectedly null.Also, Vala has code contracts. This is starting to come in C# 4, but the way it works in Vala is that you specify requirements in short phrases as part of your function signature and they stick to the signature, so that when you inherit it, it has exactly the same code contract as the base one, or when you inherit from an interface, you have to match the signature exactly. Just using those makes you think a bit more about how you’re writing your method, it’s not an afterthought when you’ve got contracts from base classes given to you, you can’t change it. Which I think is a lot nicer than the way C# handles it. When are those actually checked?They’re checked both at compile and run-time. The compile-time checking isn’t very strong yet, it’s quite a new feature in the compiler, and because it compiles down to C, you can write C code and interface with your methods, so you can bypass that compile-time check anyway. So there’s an extra runtime check, and if you violate one of the contracts at runtime, it’s game over for your program, there’s no exception to catch, it’s just goodbye!One thing I dislike about C# is the exceptions. You write a bit of code and fifty exceptions could come from any point in your ten lines, and you can’t mentally model how those exceptions are going to come out, and you can’t even predict them based on the functions you’re calling, because if you’ve accidentally got a derived class there instead of a base class, that can throw a completely different set of exceptions. So I’ve got no way of mentally modelling those, whereas in Vala they’re checked like Java, so you know only these exceptions can come out. You know in advance the error conditions.I think Raymond Chen on Old New Thing says “the only thing you know when you throw an exception is that you’re in an invalid state somewhere in your program, so just kill it and be done with it!”You said you’ve also learnt bits of Python. How did you find that compared to Vala and C#?Very different because of the dynamic typing. I’ve been writing a website for my own use. I’m quite into photography, so I take photos off my camera, post-process them, dump them in a file, and I get a webpage with all my thumbnails. So sort of like Picassa, but written by myself because I wanted something to learn Python with. There are some things that are really nice, I just found it really difficult to cope with the fact that I’m not quite sure what this object type that I’m passed is, I might not ever be sure, so it can randomly blow up on me. But once I train myself to ignore that and just say “well, I’m fairly sure it’s going to be something that looks like this, so I’ll use it like this”, then it’s quite nice.Any particular features that you’ve appreciated?I don’t like any particular feature, it’s just very straightforward to work with. It’s very quick to write something in, particularly as you don’t have to worry that you’ve changed something that affects a different part of the program. If you have, then that part blows up, but I can get this part working right now.If you were doing a big project, would you be willing to do it in Python rather than C# or Vala?I think I might be willing to try something bigger or long term with Python. We’re currently doing an ASP.NET MVC project on C#, and I don’t like the amount of reflection. There’s a lot of magic that pulls values out, and it’s all done under the scenes. It’s almost managed to put a dynamic type system on top of C#, which in many ways destroys the language to me, whereas if you’re already in a dynamic language, having things done dynamically is much more natural. In many ways, you get the worst of both worlds. I think for web projects, I would go with Python again, whereas for anything desktop, command-line or GUI-based, I’d probably go for C# or Vala, depending on what environment I’m in.It’s the fact that you can gain from the strong typing in ways that you can’t so much on the web app. Or, in a web app, you have to use dynamic typing at some point, or you have to write a hell of a lot of boilerplate, and I’d rather use the dynamic typing than write the boilerplate.What do you think separates great programmers from everyone else?Probably design choices. Choosing to write it a piece of code one way or another. For any given program you ask me to write, I could probably do it five thousand ways. A programmer who is capable will see four or five of them, and choose one of the better ones. The excellent programmer will see the largest proportion and manage to pick the best one very quickly without having to think too much about it. I think that’s probably what separates, is the speed at which they can see what’s the best path to write the program in. More Red Gater Coder interviews

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Using Rich Text Editor (WYSIWYG) in ASP.NET MVC

- by imran_ku07

Introduction: In ASP.NET MVC forum I found some question regarding a sample HTML Rich Text Box Editor(also known as wysiwyg).So i decided to create a sample ASP.NET MVC web application which will use a Rich Text Box Editor. There are are lot of Html Editors are available, but for creating a sample application, i decided to use cross-browser WYSIWYG editor from openwebware. In this article I will discuss what changes needed to work this editor with ASP.NET MVC. Also I had attached the sample application for download at http://www.speedfile.org/155076. Also note that I will only show the important features, not discuss every feature in detail. Description: So Let's start create a sample ASP.NET MVC application. You need to add the following script files, jquery-1.3.2.min.js jquery_form.js wysiwyg.js wysiwyg-settings.js wysiwyg-popup.js Just put these files inside Scripts folder. Also put wysiwyg.css in your Content Folder and add the following folders in your project addons popups Also create a empty folder Uploads to store the uploaded images. Next open wysiwyg.js and set your configuration // Images Directory this.ImagesDir = "/addons/imagelibrary/images/"; // Popups Directory this.PopupsDir = "/popups/"; // CSS Directory File this.CSSFile = "/Content/wysiwyg.css"; Next create a simple View TextEditor.aspx inside View / Home Folder and add the folllowing HTML. <%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html > <head runat="server"> <title>TextEditor</title> <script src="../../Scripts/wysiwyg.js" type="text/javascript"></script> <script src="../../Scripts/wysiwyg-settings.js" type="text/javascript"></script> <script type="text/javascript"> WYSIWYG.attach('text', full); </script> </head> <body> <% using (Html.BeginForm()){ %> <textarea id="text" name="test2" style="width:850px;height:200px;"> </textarea> <input type="submit" value="submit" /> <%} %> </body> </html> Here i have just added a text area control and a submit button inside a form. Note the id of text area and WYSIWYG.attach function's first parameter is same and next to watch is the HomeController.cs using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.Mvc; using System.IO; namespace HtmlTextEditor.Controllers { [HandleError] public class HomeController : Controller { public ActionResult Index() { ViewData["Message"] = "Welcome to ASP.NET MVC!"; return View(); } public ActionResult About() { return View(); } public ActionResult TextEditor() { return View(); } [AcceptVerbs(HttpVerbs.Post)] [ValidateInput(false)] public ActionResult TextEditor(string test2) { Session["html"] = test2; return RedirectToAction("Index"); } public ActionResult UploadImage() { if (Request.Files[0].FileName != "") { Request.Files[0].SaveAs(Server.MapPath("~/Uploads/" + Path.GetFileName(Request.Files[0].FileName))); return Content(Url.Content("~/Uploads/" + Path.GetFileName(Request.Files[0].FileName))); } return Content("a"); } } } So simple code, just save the posted Html into Session. Here the parameter of TextArea action is test2 which is same as textarea control name of TextArea.aspx View. Also note ValidateInputAttribute is false, so it's up to you to defends against XSS. Also there is an Action method which simply saves the file inside Upload Folder. I am uploading the file using Jquery Form Plugin. Here is the code which is found in insert_image.html inside addons folder, function ChangeImage() { var myform=document.getElementById("formUpload"); $(myform).ajaxSubmit({success: function(responseText){ insertImage(responseText); window.close(); } }); } and here is the Index View which simply renders the html of Editor which was saved in Session <%@ Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage" %> <asp:Content ID="indexTitle" ContentPlaceHolderID="TitleContent" runat="server"> Home Page </asp:Content> <asp:Content ID="indexContent" ContentPlaceHolderID="MainContent" runat="server"> <h2><%= Html.Encode(ViewData["Message"]) %></h2> <p> To learn more about ASP.NET MVC visit <a href="http://asp.net/mvc" title="ASP.NET MVC Website">http://asp.net/mvc</a>. </p> <%if (Session["html"] != null){ Response.Write(Session["html"].ToString()); } %> </asp:Content> Summary: Hopefully you will enjoy this article. Just download the code and see the effect. From security point, you must handle the XSS attack your self. I had uploaded the sample application in http://www.speedfile.org/155076

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Advanced TSQL Tuning: Why Internals Knowledge Matters

- by Paul White

There is much more to query tuning than reducing logical reads and adding covering nonclustered indexes. Query tuning is not complete as soon as the query returns results quickly in the development or test environments. In production, your query will compete for memory, CPU, locks, I/O and other resources on the server. Today’s entry looks at some tuning considerations that are often overlooked, and shows how deep internals knowledge can help you write better TSQL. As always, we’ll need some example data. In fact, we are going to use three tables today, each of which is structured like this: Each table has 50,000 rows made up of an INTEGER id column and a padding column containing 3,999 characters in every row. The only difference between the three tables is in the type of the padding column: the first table uses CHAR(3999), the second uses VARCHAR(MAX), and the third uses the deprecated TEXT type. A script to create a database with the three tables and load the sample data follows: USE master; GO IF DB_ID('SortTest') IS NOT NULL DROP DATABASE SortTest; GO CREATE DATABASE SortTest COLLATE LATIN1_GENERAL_BIN; GO ALTER DATABASE SortTest MODIFY FILE ( NAME = 'SortTest', SIZE = 3GB, MAXSIZE = 3GB ); GO ALTER DATABASE SortTest MODIFY FILE ( NAME = 'SortTest_log', SIZE = 256MB, MAXSIZE = 1GB, FILEGROWTH = 128MB ); GO ALTER DATABASE SortTest SET ALLOW_SNAPSHOT_ISOLATION OFF ; ALTER DATABASE SortTest SET AUTO_CLOSE OFF ; ALTER DATABASE SortTest SET AUTO_CREATE_STATISTICS ON ; ALTER DATABASE SortTest SET AUTO_SHRINK OFF ; ALTER DATABASE SortTest SET AUTO_UPDATE_STATISTICS ON ; ALTER DATABASE SortTest SET AUTO_UPDATE_STATISTICS_ASYNC ON ; ALTER DATABASE SortTest SET PARAMETERIZATION SIMPLE ; ALTER DATABASE SortTest SET READ_COMMITTED_SNAPSHOT OFF ; ALTER DATABASE SortTest SET MULTI_USER ; ALTER DATABASE SortTest SET RECOVERY SIMPLE ; USE SortTest; GO CREATE TABLE dbo.TestCHAR ( id INTEGER IDENTITY (1,1) NOT NULL, padding CHAR(3999) NOT NULL, CONSTRAINT [PK dbo.TestCHAR (id)] PRIMARY KEY CLUSTERED (id), ) ; CREATE TABLE dbo.TestMAX ( id INTEGER IDENTITY (1,1) NOT NULL, padding VARCHAR(MAX) NOT NULL, CONSTRAINT [PK dbo.TestMAX (id)] PRIMARY KEY CLUSTERED (id), ) ; CREATE TABLE dbo.TestTEXT ( id INTEGER IDENTITY (1,1) NOT NULL, padding TEXT NOT NULL, CONSTRAINT [PK dbo.TestTEXT (id)] PRIMARY KEY CLUSTERED (id), ) ; -- ============= -- Load TestCHAR (about 3s) -- ============= INSERT INTO dbo.TestCHAR WITH (TABLOCKX) ( padding ) SELECT padding = REPLICATE(CHAR(65 + (Data.n % 26)), 3999) FROM ( SELECT TOP (50000) n = ROW_NUMBER() OVER (ORDER BY (SELECT 0)) - 1 FROM master.sys.columns C1, master.sys.columns C2, master.sys.columns C3 ORDER BY n ASC ) AS Data ORDER BY Data.n ASC ; -- ============ -- Load TestMAX (about 3s) -- ============ INSERT INTO dbo.TestMAX WITH (TABLOCKX) ( padding ) SELECT CONVERT(VARCHAR(MAX), padding) FROM dbo.TestCHAR ORDER BY id ; -- ============= -- Load TestTEXT (about 5s) -- ============= INSERT INTO dbo.TestTEXT WITH (TABLOCKX) ( padding ) SELECT CONVERT(TEXT, padding) FROM dbo.TestCHAR ORDER BY id ; -- ========== -- Space used -- ========== -- EXECUTE sys.sp_spaceused @objname = 'dbo.TestCHAR'; EXECUTE sys.sp_spaceused @objname = 'dbo.TestMAX'; EXECUTE sys.sp_spaceused @objname = 'dbo.TestTEXT'; ; CHECKPOINT ; That takes around 15 seconds to run, and shows the space allocated to each table in its output: To illustrate the points I want to make today, the example task we are going to set ourselves is to return a random set of 150 rows from each table. The basic shape of the test query is the same for each of the three test tables: SELECT TOP (150) T.id, T.padding FROM dbo.Test AS T ORDER BY NEWID() OPTION (MAXDOP 1) ; Test 1 – CHAR(3999) Running the template query shown above using the TestCHAR table as the target, we find that the query takes around 5 seconds to return its results. This seems slow, considering that the table only has 50,000 rows. Working on the assumption that generating a GUID for each row is a CPU-intensive operation, we might try enabling parallelism to see if that speeds up the response time. Running the query again (but without the MAXDOP 1 hint) on a machine with eight logical processors, the query now takes 10 seconds to execute – twice as long as when run serially. Rather than attempting further guesses at the cause of the slowness, let’s go back to serial execution and add some monitoring. The script below monitors STATISTICS IO output and the amount of tempdb used by the test query. We will also run a Profiler trace to capture any warnings generated during query execution. DECLARE @read BIGINT, @write BIGINT ; SELECT @read = SUM(num_of_bytes_read), @write = SUM(num_of_bytes_written) FROM tempdb.sys.database_files AS DBF JOIN sys.dm_io_virtual_file_stats(2, NULL) AS FS ON FS.file_id = DBF.file_id WHERE DBF.type_desc = 'ROWS' ; SET STATISTICS IO ON ; SELECT TOP (150) TC.id, TC.padding FROM dbo.TestCHAR AS TC ORDER BY NEWID() OPTION (MAXDOP 1) ; SET STATISTICS IO OFF ; SELECT tempdb_read_MB = (SUM(num_of_bytes_read) - @read) / 1024. / 1024., tempdb_write_MB = (SUM(num_of_bytes_written) - @write) / 1024. / 1024., internal_use_MB = ( SELECT internal_objects_alloc_page_count / 128.0 FROM sys.dm_db_task_space_usage WHERE session_id = @@SPID ) FROM tempdb.sys.database_files AS DBF JOIN sys.dm_io_virtual_file_stats(2, NULL) AS FS ON FS.file_id = DBF.file_id WHERE DBF.type_desc = 'ROWS' ; Let’s take a closer look at the statistics and query plan generated from this: Following the flow of the data from right to left, we see the expected 50,000 rows emerging from the Clustered Index Scan, with a total estimated size of around 191MB. The Compute Scalar adds a column containing a random GUID (generated from the NEWID() function call) for each row. With this extra column in place, the size of the data arriving at the Sort operator is estimated to be 192MB. Sort is a blocking operator – it has to examine all of the rows on its input before it can produce its first row of output (the last row received might sort first). This characteristic means that Sort requires a memory grant – memory allocated for the query’s use by SQL Server just before execution starts. In this case, the Sort is the only memory-consuming operator in the plan, so it has access to the full 243MB (248,696KB) of memory reserved by SQL Server for this query execution. Notice that the memory grant is significantly larger than the expected size of the data to be sorted. SQL Server uses a number of techniques to speed up sorting, some of which sacrifice size for comparison speed. Sorts typically require a very large number of comparisons, so this is usually a very effective optimization. One of the drawbacks is that it is not possible to exactly predict the sort space needed, as it depends on the data itself. SQL Server takes an educated guess based on data types, sizes, and the number of rows expected, but the algorithm is not perfect. In spite of the large memory grant, the Profiler trace shows a Sort Warning event (indicating that the sort ran out of memory), and the tempdb usage monitor shows that 195MB of tempdb space was used – all of that for system use. The 195MB represents physical write activity on tempdb, because SQL Server strictly enforces memory grants – a query cannot ‘cheat’ and effectively gain extra memory by spilling to tempdb pages that reside in memory. Anyway, the key point here is that it takes a while to write 195MB to disk, and this is the main reason that the query takes 5 seconds overall. If you are wondering why using parallelism made the problem worse, consider that eight threads of execution result in eight concurrent partial sorts, each receiving one eighth of the memory grant. The eight sorts all spilled to tempdb, resulting in inefficiencies as the spilled sorts competed for disk resources. More importantly, there are specific problems at the point where the eight partial results are combined, but I’ll cover that in a future post. CHAR(3999) Performance Summary: 5 seconds elapsed time 243MB memory grant 195MB tempdb usage 192MB estimated sort set 25,043 logical reads Sort Warning Test 2 – VARCHAR(MAX) We’ll now run exactly the same test (with the additional monitoring) on the table using a VARCHAR(MAX) padding column: DECLARE @read BIGINT, @write BIGINT ; SELECT @read = SUM(num_of_bytes_read), @write = SUM(num_of_bytes_written) FROM tempdb.sys.database_files AS DBF JOIN sys.dm_io_virtual_file_stats(2, NULL) AS FS ON FS.file_id = DBF.file_id WHERE DBF.type_desc = 'ROWS' ; SET STATISTICS IO ON ; SELECT TOP (150) TM.id, TM.padding FROM dbo.TestMAX AS TM ORDER BY NEWID() OPTION (MAXDOP 1) ; SET STATISTICS IO OFF ; SELECT tempdb_read_MB = (SUM(num_of_bytes_read) - @read) / 1024. / 1024., tempdb_write_MB = (SUM(num_of_bytes_written) - @write) / 1024. / 1024., internal_use_MB = ( SELECT internal_objects_alloc_page_count / 128.0 FROM sys.dm_db_task_space_usage WHERE session_id = @@SPID ) FROM tempdb.sys.database_files AS DBF JOIN sys.dm_io_virtual_file_stats(2, NULL) AS FS ON FS.file_id = DBF.file_id WHERE DBF.type_desc = 'ROWS' ; This time the query takes around 8 seconds to complete (3 seconds longer than Test 1). Notice that the estimated row and data sizes are very slightly larger, and the overall memory grant has also increased very slightly to 245MB. The most marked difference is in the amount of tempdb space used – this query wrote almost 391MB of sort run data to the physical tempdb file. Don’t draw any general conclusions about VARCHAR(MAX) versus CHAR from this – I chose the length of the data specifically to expose this edge case. In most cases, VARCHAR(MAX) performs very similarly to CHAR – I just wanted to make test 2 a bit more exciting. MAX Performance Summary: 8 seconds elapsed time 245MB memory grant 391MB tempdb usage 193MB estimated sort set 25,043 logical reads Sort warning Test 3 – TEXT The same test again, but using the deprecated TEXT data type for the padding column: DECLARE @read BIGINT, @write BIGINT ; SELECT @read = SUM(num_of_bytes_read), @write = SUM(num_of_bytes_written) FROM tempdb.sys.database_files AS DBF JOIN sys.dm_io_virtual_file_stats(2, NULL) AS FS ON FS.file_id = DBF.file_id WHERE DBF.type_desc = 'ROWS' ; SET STATISTICS IO ON ; SELECT TOP (150) TT.id, TT.padding FROM dbo.TestTEXT AS TT ORDER BY NEWID() OPTION (MAXDOP 1, RECOMPILE) ; SET STATISTICS IO OFF ; SELECT tempdb_read_MB = (SUM(num_of_bytes_read) - @read) / 1024. / 1024., tempdb_write_MB = (SUM(num_of_bytes_written) - @write) / 1024. / 1024., internal_use_MB = ( SELECT internal_objects_alloc_page_count / 128.0 FROM sys.dm_db_task_space_usage WHERE session_id = @@SPID ) FROM tempdb.sys.database_files AS DBF JOIN sys.dm_io_virtual_file_stats(2, NULL) AS FS ON FS.file_id = DBF.file_id WHERE DBF.type_desc = 'ROWS' ; This time the query runs in 500ms. If you look at the metrics we have been checking so far, it’s not hard to understand why: TEXT Performance Summary: 0.5 seconds elapsed time 9MB memory grant 5MB tempdb usage 5MB estimated sort set 207 logical reads 596 LOB logical reads Sort warning SQL Server’s memory grant algorithm still underestimates the memory needed to perform the sorting operation, but the size of the data to sort is so much smaller (5MB versus 193MB previously) that the spilled sort doesn’t matter very much. Why is the data size so much smaller? The query still produces the correct results – including the large amount of data held in the padding column – so what magic is being performed here? TEXT versus MAX Storage The answer lies in how columns of the TEXT data type are stored. By default, TEXT data is stored off-row in separate LOB pages – which explains why this is the first query we have seen that records LOB logical reads in its STATISTICS IO output. You may recall from my last post that LOB data leaves an in-row pointer to the separate storage structure holding the LOB data. SQL Server can see that the full LOB value is not required by the query plan until results are returned, so instead of passing the full LOB value down the plan from the Clustered Index Scan, it passes the small in-row structure instead. SQL Server estimates that each row coming from the scan will be 79 bytes long – 11 bytes for row overhead, 4 bytes for the integer id column, and 64 bytes for the LOB pointer (in fact the pointer is rather smaller – usually 16 bytes – but the details of that don’t really matter right now). OK, so this query is much more efficient because it is sorting a very much smaller data set – SQL Server delays retrieving the LOB data itself until after the Sort starts producing its 150 rows. The question that normally arises at this point is: Why doesn’t SQL Server use the same trick when the padding column is defined as VARCHAR(MAX)? The answer is connected with the fact that if the actual size of the VARCHAR(MAX) data is 8000 bytes or less, it is usually stored in-row in exactly the same way as for a VARCHAR(8000) column – MAX data only moves off-row into LOB storage when it exceeds 8000 bytes. The default behaviour of the TEXT type is to be stored off-row by default, unless the ‘text in row’ table option is set suitably and there is room on the page. There is an analogous (but opposite) setting to control the storage of MAX data – the ‘large value types out of row’ table option. By enabling this option for a table, MAX data will be stored off-row (in a LOB structure) instead of in-row. SQL Server Books Online has good coverage of both options in the topic In Row Data. The MAXOOR Table The essential difference, then, is that MAX defaults to in-row storage, and TEXT defaults to off-row (LOB) storage. You might be thinking that we could get the same benefits seen for the TEXT data type by storing the VARCHAR(MAX) values off row – so let’s look at that option now. This script creates a fourth table, with the VARCHAR(MAX) data stored off-row in LOB pages: CREATE TABLE dbo.TestMAXOOR ( id INTEGER IDENTITY (1,1) NOT NULL, padding VARCHAR(MAX) NOT NULL, CONSTRAINT [PK dbo.TestMAXOOR (id)] PRIMARY KEY CLUSTERED (id), ) ; EXECUTE sys.sp_tableoption @TableNamePattern = N'dbo.TestMAXOOR', @OptionName = 'large value types out of row', @OptionValue = 'true' ; SELECT large_value_types_out_of_row FROM sys.tables WHERE [schema_id] = SCHEMA_ID(N'dbo') AND name = N'TestMAXOOR' ; INSERT INTO dbo.TestMAXOOR WITH (TABLOCKX) ( padding ) SELECT SPACE(0) FROM dbo.TestCHAR ORDER BY id ; UPDATE TM WITH (TABLOCK) SET padding.WRITE (TC.padding, NULL, NULL) FROM dbo.TestMAXOOR AS TM JOIN dbo.TestCHAR AS TC ON TC.id = TM.id ; EXECUTE sys.sp_spaceused @objname = 'dbo.TestMAXOOR' ; CHECKPOINT ; Test 4 – MAXOOR We can now re-run our test on the MAXOOR (MAX out of row) table: DECLARE @read BIGINT, @write BIGINT ; SELECT @read = SUM(num_of_bytes_read), @write = SUM(num_of_bytes_written) FROM tempdb.sys.database_files AS DBF JOIN sys.dm_io_virtual_file_stats(2, NULL) AS FS ON FS.file_id = DBF.file_id WHERE DBF.type_desc = 'ROWS' ; SET STATISTICS IO ON ; SELECT TOP (150) MO.id, MO.padding FROM dbo.TestMAXOOR AS MO ORDER BY NEWID() OPTION (MAXDOP 1, RECOMPILE) ; SET STATISTICS IO OFF ; SELECT tempdb_read_MB = (SUM(num_of_bytes_read) - @read) / 1024. / 1024., tempdb_write_MB = (SUM(num_of_bytes_written) - @write) / 1024. / 1024., internal_use_MB = ( SELECT internal_objects_alloc_page_count / 128.0 FROM sys.dm_db_task_space_usage WHERE session_id = @@SPID ) FROM tempdb.sys.database_files AS DBF JOIN sys.dm_io_virtual_file_stats(2, NULL) AS FS ON FS.file_id = DBF.file_id WHERE DBF.type_desc = 'ROWS' ; TEXT Performance Summary: 0.3 seconds elapsed time 245MB memory grant 0MB tempdb usage 193MB estimated sort set 207 logical reads 446 LOB logical reads No sort warning The query runs very quickly – slightly faster than Test 3, and without spilling the sort to tempdb (there is no sort warning in the trace, and the monitoring query shows zero tempdb usage by this query). SQL Server is passing the in-row pointer structure down the plan and only looking up the LOB value on the output side of the sort. The Hidden Problem There is still a huge problem with this query though – it requires a 245MB memory grant. No wonder the sort doesn’t spill to tempdb now – 245MB is about 20 times more memory than this query actually requires to sort 50,000 records containing LOB data pointers. Notice that the estimated row and data sizes in the plan are the same as in test 2 (where the MAX data was stored in-row). The optimizer assumes that MAX data is stored in-row, regardless of the sp_tableoption setting ‘large value types out of row’. Why? Because this option is dynamic – changing it does not immediately force all MAX data in the table in-row or off-row, only when data is added or actually changed. SQL Server does not keep statistics to show how much MAX or TEXT data is currently in-row, and how much is stored in LOB pages. This is an annoying limitation, and one which I hope will be addressed in a future version of the product. So why should we worry about this? Excessive memory grants reduce concurrency and may result in queries waiting on the RESOURCE_SEMAPHORE wait type while they wait for memory they do not need. 245MB is an awful lot of memory, especially on 32-bit versions where memory grants cannot use AWE-mapped memory. Even on a 64-bit server with plenty of memory, do you really want a single query to consume 0.25GB of memory unnecessarily? That’s 32,000 8KB pages that might be put to much better use. The Solution The answer is not to use the TEXT data type for the padding column. That solution happens to have better performance characteristics for this specific query, but it still results in a spilled sort, and it is hard to recommend the use of a data type which is scheduled for removal. I hope it is clear to you that the fundamental problem here is that SQL Server sorts the whole set arriving at a Sort operator. Clearly, it is not efficient to sort the whole table in memory just to return 150 rows in a random order. The TEXT example was more efficient because it dramatically reduced the size of the set that needed to be sorted. We can do the same thing by selecting 150 unique keys from the table at random (sorting by NEWID() for example) and only then retrieving the large padding column values for just the 150 rows we need. The following script implements that idea for all four tables: SET STATISTICS IO ON ; WITH TestTable AS ( SELECT * FROM dbo.TestCHAR ), TopKeys AS ( SELECT TOP (150) id FROM TestTable ORDER BY NEWID() ) SELECT T1.id, T1.padding FROM TestTable AS T1 WHERE T1.id = ANY (SELECT id FROM TopKeys) OPTION (MAXDOP 1) ; WITH TestTable AS ( SELECT * FROM dbo.TestMAX ), TopKeys AS ( SELECT TOP (150) id FROM TestTable ORDER BY NEWID() ) SELECT T1.id, T1.padding FROM TestTable AS T1 WHERE T1.id IN (SELECT id FROM TopKeys) OPTION (MAXDOP 1) ; WITH TestTable AS ( SELECT * FROM dbo.TestTEXT ), TopKeys AS ( SELECT TOP (150) id FROM TestTable ORDER BY NEWID() ) SELECT T1.id, T1.padding FROM TestTable AS T1 WHERE T1.id IN (SELECT id FROM TopKeys) OPTION (MAXDOP 1) ; WITH TestTable AS ( SELECT * FROM dbo.TestMAXOOR ), TopKeys AS ( SELECT TOP (150) id FROM TestTable ORDER BY NEWID() ) SELECT T1.id, T1.padding FROM TestTable AS T1 WHERE T1.id IN (SELECT id FROM TopKeys) OPTION (MAXDOP 1) ; SET STATISTICS IO OFF ; All four queries now return results in much less than a second, with memory grants between 6 and 12MB, and without spilling to tempdb. The small remaining inefficiency is in reading the id column values from the clustered primary key index. As a clustered index, it contains all the in-row data at its leaf. The CHAR and VARCHAR(MAX) tables store the padding column in-row, so id values are separated by a 3999-character column, plus row overhead. The TEXT and MAXOOR tables store the padding values off-row, so id values in the clustered index leaf are separated by the much-smaller off-row pointer structure. This difference is reflected in the number of logical page reads performed by the four queries: Table 'TestCHAR' logical reads 25511 lob logical reads 000 Table 'TestMAX'. logical reads 25511 lob logical reads 000 Table 'TestTEXT' logical reads 00412 lob logical reads 597 Table 'TestMAXOOR' logical reads 00413 lob logical reads 446 We can increase the density of the id values by creating a separate nonclustered index on the id column only. This is the same key as the clustered index, of course, but the nonclustered index will not include the rest of the in-row column data. CREATE UNIQUE NONCLUSTERED INDEX uq1 ON dbo.TestCHAR (id); CREATE UNIQUE NONCLUSTERED INDEX uq1 ON dbo.TestMAX (id); CREATE UNIQUE NONCLUSTERED INDEX uq1 ON dbo.TestTEXT (id); CREATE UNIQUE NONCLUSTERED INDEX uq1 ON dbo.TestMAXOOR (id); The four queries can now use the very dense nonclustered index to quickly scan the id values, sort them by NEWID(), select the 150 ids we want, and then look up the padding data. The logical reads with the new indexes in place are: Table 'TestCHAR' logical reads 835 lob logical reads 0 Table 'TestMAX' logical reads 835 lob logical reads 0 Table 'TestTEXT' logical reads 686 lob logical reads 597 Table 'TestMAXOOR' logical reads 686 lob logical reads 448 With the new index, all four queries use the same query plan (click to enlarge): Performance Summary: 0.3 seconds elapsed time 6MB memory grant 0MB tempdb usage 1MB sort set 835 logical reads (CHAR, MAX) 686 logical reads (TEXT, MAXOOR) 597 LOB logical reads (TEXT) 448 LOB logical reads (MAXOOR) No sort warning I’ll leave it as an exercise for the reader to work out why trying to eliminate the Key Lookup by adding the padding column to the new nonclustered indexes would be a daft idea Conclusion This post is not about tuning queries that access columns containing big strings. It isn’t about the internal differences between TEXT and MAX data types either. It isn’t even about the cool use of UPDATE .WRITE used in the MAXOOR table load. No, this post is about something else: Many developers might not have tuned our starting example query at all – 5 seconds isn’t that bad, and the original query plan looks reasonable at first glance. Perhaps the NEWID() function would have been blamed for ‘just being slow’ – who knows. 5 seconds isn’t awful – unless your users expect sub-second responses – but using 250MB of memory and writing 200MB to tempdb certainly is! If ten sessions ran that query at the same time in production that’s 2.5GB of memory usage and 2GB hitting tempdb. Of course, not all queries can be rewritten to avoid large memory grants and sort spills using the key-lookup technique in this post, but that’s not the point either. The point of this post is that a basic understanding of execution plans is not enough. Tuning for logical reads and adding covering indexes is not enough. If you want to produce high-quality, scalable TSQL that won’t get you paged as soon as it hits production, you need a deep understanding of execution plans, and as much accurate, deep knowledge about SQL Server as you can lay your hands on. The advanced database developer has a wide range of tools to use in writing queries that perform well in a range of circumstances. By the way, the examples in this post were written for SQL Server 2008. They will run on 2005 and demonstrate the same principles, but you won’t get the same figures I did because 2005 had a rather nasty bug in the Top N Sort operator. Fair warning: if you do decide to run the scripts on a 2005 instance (particularly the parallel query) do it before you head out for lunch… This post is dedicated to the people of Christchurch, New Zealand. © 2011 Paul White email: @[email protected] twitter: @SQL_Kiwi

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value types in the vm

- by john.rose

value types in the vm p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Times} p.p2 {margin: 0.0px 0.0px 14.0px 0.0px; font: 14.0px Times} p.p3 {margin: 0.0px 0.0px 12.0px 0.0px; font: 14.0px Times} p.p4 {margin: 0.0px 0.0px 15.0px 0.0px; font: 14.0px Times} p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Courier} p.p6 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Courier; min-height: 17.0px} p.p7 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Times; min-height: 18.0px} p.p8 {margin: 0.0px 0.0px 0.0px 36.0px; text-indent: -36.0px; font: 14.0px Times; min-height: 18.0px} p.p9 {margin: 0.0px 0.0px 12.0px 0.0px; font: 14.0px Times; min-height: 18.0px} p.p10 {margin: 0.0px 0.0px 12.0px 0.0px; font: 14.0px Times; color: #000000} li.li1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Times} li.li7 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Times; min-height: 18.0px} span.s1 {font: 14.0px Courier} span.s2 {color: #000000} span.s3 {font: 14.0px Courier; color: #000000} ol.ol1 {list-style-type: decimal} Or, enduring values for a changing world. Introduction A value type is a data type which, generally speaking, is designed for being passed by value in and out of methods, and stored by value in data structures. The only value types which the Java language directly supports are the eight primitive types. Java indirectly and approximately supports value types, if they are implemented in terms of classes. For example, both Integer and String may be viewed as value types, especially if their usage is restricted to avoid operations appropriate to Object. In this note, we propose a definition of value types in terms of a design pattern for Java classes, accompanied by a set of usage restrictions. We also sketch the relation of such value types to tuple types (which are a JVM-level notion), and point out JVM optimizations that can apply to value types. This note is a thought experiment to extend the JVM’s performance model in support of value types. The demonstration has two phases. Initially the extension can simply use design patterns, within the current bytecode architecture, and in today’s Java language. But if the performance model is to be realized in practice, it will probably require new JVM bytecode features, changes to the Java language, or both. We will look at a few possibilities for these new features. An Axiom of Value In the context of the JVM, a value type is a data type equipped with construction, assignment, and equality operations, and a set of typed components, such that, whenever two variables of the value type produce equal corresponding values for their components, the values of the two variables cannot be distinguished by any JVM operation. Here are some corollaries: A value type is immutable, since otherwise a copy could be constructed and the original could be modified in one of its components, allowing the copies to be distinguished. Changing the component of a value type requires construction of a new value. The equals and hashCode operations are strictly component-wise. If a value type is represented by a JVM reference, that reference cannot be successfully synchronized on, and cannot be usefully compared for reference equality. A value type can be viewed in terms of what it doesn’t do. We can say that a value type omits all value-unsafe operations, which could violate the constraints on value types. These operations, which are ordinarily allowed for Java object types, are pointer equality comparison (the acmp instruction), synchronization (the monitor instructions), all the wait and notify methods of class Object, and non-trivial finalize methods. The clone method is also value-unsafe, although for value types it could be treated as the identity function. Finally, and most importantly, any side effect on an object (however visible) also counts as an value-unsafe operation. A value type may have methods, but such methods must not change the components of the value. It is reasonable and useful to define methods like toString, equals, and hashCode on value types, and also methods which are specifically valuable to users of the value type. Representations of Value Value types have two natural representations in the JVM, unboxed and boxed. An unboxed value consists of the components, as simple variables. For example, the complex number x=(1+2i), in rectangular coordinate form, may be represented in unboxed form by the following pair of variables: /*Complex x = Complex.valueOf(1.0, 2.0):*/ double x_re = 1.0, x_im = 2.0; These variables might be locals, parameters, or fields. Their association as components of a single value is not defined to the JVM. Here is a sample computation which computes the norm of the difference between two complex numbers: double distance(/*Complex x:*/ double x_re, double x_im, /*Complex y:*/ double y_re, double y_im) { /*Complex z = x.minus(y):*/ double z_re = x_re - y_re, z_im = x_im - y_im; /*return z.abs():*/ return Math.sqrt(z_re*z_re + z_im*z_im); } A boxed representation groups component values under a single object reference. The reference is to a ‘wrapper class’ that carries the component values in its fields. (A primitive type can naturally be equated with a trivial value type with just one component of that type. In that view, the wrapper class Integer can serve as a boxed representation of value type int.) The unboxed representation of complex numbers is practical for many uses, but it fails to cover several major use cases: return values, array elements, and generic APIs. The two components of a complex number cannot be directly returned from a Java function, since Java does not support multiple return values. The same story applies to array elements: Java has no ’array of structs’ feature. (Double-length arrays are a possible workaround for complex numbers, but not for value types with heterogeneous components.) By generic APIs I mean both those which use generic types, like Arrays.asList and those which have special case support for primitive types, like String.valueOf and PrintStream.println. Those APIs do not support unboxed values, and offer some problems to boxed values. Any ’real’ JVM type should have a story for returns, arrays, and API interoperability. The basic problem here is that value types fall between primitive types and object types. Value types are clearly more complex than primitive types, and object types are slightly too complicated. Objects are a little bit dangerous to use as value carriers, since object references can be compared for pointer equality, and can be synchronized on. Also, as many Java programmers have observed, there is often a performance cost to using wrapper objects, even on modern JVMs. Even so, wrapper classes are a good starting point for talking about value types. If there were a set of structural rules and restrictions which would prevent value-unsafe operations on value types, wrapper classes would provide a good notation for defining value types. This note attempts to define such rules and restrictions. Let’s Start Coding Now it is time to look at some real code. Here is a definition, written in Java, of a complex number value type. @ValueSafe public final class Complex implements java.io.Serializable { // immutable component structure: public final double re, im; private Complex(double re, double im) { this.re = re; this.im = im; } // interoperability methods: public String toString() { return "Complex("+re+","+im+")"; } public List<Double> asList() { return Arrays.asList(re, im); } public boolean equals(Complex c) { return re == c.re && im == c.im; } public boolean equals(@ValueSafe Object x) { return x instanceof Complex && equals((Complex) x); } public int hashCode() { return 31*Double.valueOf(re).hashCode() + Double.valueOf(im).hashCode(); } // factory methods: public static Complex valueOf(double re, double im) { return new Complex(re, im); } public Complex changeRe(double re2) { return valueOf(re2, im); } public Complex changeIm(double im2) { return valueOf(re, im2); } public static Complex cast(@ValueSafe Object x) { return x == null ? ZERO : (Complex) x; } // utility methods and constants: public Complex plus(Complex c) { return new Complex(re+c.re, im+c.im); } public Complex minus(Complex c) { return new Complex(re-c.re, im-c.im); } public double abs() { return Math.sqrt(re*re + im*im); } public static final Complex PI = valueOf(Math.PI, 0.0); public static final Complex ZERO = valueOf(0.0, 0.0); } This is not a minimal definition, because it includes some utility methods and other optional parts. The essential elements are as follows: The class is marked as a value type with an annotation. The class is final, because it does not make sense to create subclasses of value types. The fields of the class are all non-private and final. (I.e., the type is immutable and structurally transparent.) From the supertype Object, all public non-final methods are overridden. The constructor is private. Beyond these bare essentials, we can observe the following features in this example, which are likely to be typical of all value types: One or more factory methods are responsible for value creation, including a component-wise valueOf method. There are utility methods for complex arithmetic and instance creation, such as plus and changeIm. There are static utility constants, such as PI. The type is serializable, using the default mechanisms. There are methods for converting to and from dynamically typed references, such as asList and cast. The Rules In order to use value types properly, the programmer must avoid value-unsafe operations. A helpful Java compiler should issue errors (or at least warnings) for code which provably applies value-unsafe operations, and should issue warnings for code which might be correct but does not provably avoid value-unsafe operations. No such compilers exist today, but to simplify our account here, we will pretend that they do exist. A value-safe type is any class, interface, or type parameter marked with the @ValueSafe annotation, or any subtype of a value-safe type. If a value-safe class is marked final, it is in fact a value type. All other value-safe classes must be abstract. The non-static fields of a value class must be non-public and final, and all its constructors must be private. Under the above rules, a standard interface could be helpful to define value types like Complex. Here is an example: @ValueSafe public interface ValueType extends java.io.Serializable { // All methods listed here must get redefined. // Definitions must be value-safe, which means // they may depend on component values only. List<? extends Object> asList(); int hashCode(); boolean equals(@ValueSafe Object c); String toString(); } //@ValueSafe inherited from supertype: public final class Complex implements ValueType { … The main advantage of such a conventional interface is that (unlike an annotation) it is reified in the runtime type system. It could appear as an element type or parameter bound, for facilities which are designed to work on value types only. More broadly, it might assist the JVM to perform dynamic enforcement of the rules for value types. Besides types, the annotation @ValueSafe can mark fields, parameters, local variables, and methods. (This is redundant when the type is also value-safe, but may be useful when the type is Object or another supertype of a value type.) Working forward from these annotations, an expression E is defined as value-safe if it satisfies one or more of the following: The type of E is a value-safe type. E names a field, parameter, or local variable whose declaration is marked @ValueSafe. E is a call to a method whose declaration is marked @ValueSafe. E is an assignment to a value-safe variable, field reference, or array reference. E is a cast to a value-safe type from a value-safe expression. E is a conditional expression E0 ? E1 : E2, and both E1 and E2 are value-safe. Assignments to value-safe expressions and initializations of value-safe names must take their values from value-safe expressions. A value-safe expression may not be the subject of a value-unsafe operation. In particular, it cannot be synchronized on, nor can it be compared with the “==” operator, not even with a null or with another value-safe type. In a program where all of these rules are followed, no value-type value will be subject to a value-unsafe operation. Thus, the prime axiom of value types will be satisfied, that no two value type will be distinguishable as long as their component values are equal. More Code To illustrate these rules, here are some usage examples for Complex: Complex pi = Complex.valueOf(Math.PI, 0); Complex zero = pi.changeRe(0); //zero = pi; zero.re = 0; ValueType vtype = pi; @SuppressWarnings("value-unsafe") Object obj = pi; @ValueSafe Object obj2 = pi; obj2 = new Object(); // ok List<Complex> clist = new ArrayList<Complex>(); clist.add(pi); // (ok assuming List.add param is @ValueSafe) List<ValueType> vlist = new ArrayList<ValueType>(); vlist.add(pi); // (ok) List<Object> olist = new ArrayList<Object>(); olist.add(pi); // warning: "value-unsafe" boolean z = pi.equals(zero); boolean z1 = (pi == zero); // error: reference comparison on value type boolean z2 = (pi == null); // error: reference comparison on value type boolean z3 = (pi == obj2); // error: reference comparison on value type synchronized (pi) { } // error: synch of value, unpredictable result synchronized (obj2) { } // unpredictable result Complex qq = pi; qq = null; // possible NPE; warning: “null-unsafe" qq = (Complex) obj; // warning: “null-unsafe" qq = Complex.cast(obj); // OK @SuppressWarnings("null-unsafe") Complex empty = null; // possible NPE qq = empty; // possible NPE (null pollution) The Payoffs It follows from this that either the JVM or the java compiler can replace boxed value-type values with unboxed ones, without affecting normal computations. Fields and variables of value types can be split into their unboxed components. Non-static methods on value types can be transformed into static methods which take the components as value parameters. Some common questions arise around this point in any discussion of value types. Why burden the programmer with all these extra rules? Why not detect programs automagically and perform unboxing transparently? The answer is that it is easy to break the rules accidently unless they are agreed to by the programmer and enforced. Automatic unboxing optimizations are tantalizing but (so far) unreachable ideal. In the current state of the art, it is possible exhibit benchmarks in which automatic unboxing provides the desired effects, but it is not possible to provide a JVM with a performance model that assures the programmer when unboxing will occur. This is why I’m writing this note, to enlist help from, and provide assurances to, the programmer. Basically, I’m shooting for a good set of user-supplied “pragmas” to frame the desired optimization. Again, the important thing is that the unboxing must be done reliably, or else programmers will have no reason to work with the extra complexity of the value-safety rules. There must be a reasonably stable performance model, wherein using a value type has approximately the same performance characteristics as writing the unboxed components as separate Java variables. There are some rough corners to the present scheme. Since Java fields and array elements are initialized to null, value-type computations which incorporate uninitialized variables can produce null pointer exceptions. One workaround for this is to require such variables to be null-tested, and the result replaced with a suitable all-zero value of the value type. That is what the “cast” method does above. Generically typed APIs like List<T> will continue to manipulate boxed values always, at least until we figure out how to do reification of generic type instances. Use of such APIs will elicit warnings until their type parameters (and/or relevant members) are annotated or typed as value-safe. Retrofitting List<T> is likely to expose flaws in the present scheme, which we will need to engineer around. Here are a couple of first approaches: public interface java.util.List<@ValueSafe T> extends Collection<T> { … public interface java.util.List<T extends Object|ValueType> extends Collection<T> { … (The second approach would require disjunctive types, in which value-safety is “contagious” from the constituent types.) With more transformations, the return value types of methods can also be unboxed. This may require significant bytecode-level transformations, and would work best in the presence of a bytecode representation for multiple value groups, which I have proposed elsewhere under the title “Tuples in the VM”. But for starters, the JVM can apply this transformation under the covers, to internally compiled methods. This would give a way to express multiple return values and structured return values, which is a significant pain-point for Java programmers, especially those who work with low-level structure types favored by modern vector and graphics processors. The lack of multiple return values has a strong distorting effect on many Java APIs. Even if the JVM fails to unbox a value, there is still potential benefit to the value type. Clustered computing systems something have copy operations (serialization or something similar) which apply implicitly to command operands. When copying JVM objects, it is extremely helpful to know when an object’s identity is important or not. If an object reference is a copied operand, the system may have to create a proxy handle which points back to the original object, so that side effects are visible. Proxies must be managed carefully, and this can be expensive. On the other hand, value types are exactly those types which a JVM can “copy and forget” with no downside. Array types are crucial to bulk data interfaces. (As data sizes and rates increase, bulk data becomes more important than scalar data, so arrays are definitely accompanying us into the future of computing.) Value types are very helpful for adding structure to bulk data, so a successful value type mechanism will make it easier for us to express richer forms of bulk data. Unboxing arrays (i.e., arrays containing unboxed values) will provide better cache and memory density, and more direct data movement within clustered or heterogeneous computing systems. They require the deepest transformations, relative to today’s JVM. There is an impedance mismatch between value-type arrays and Java’s covariant array typing, so compromises will need to be struck with existing Java semantics. It is probably worth the effort, since arrays of unboxed value types are inherently more memory-efficient than standard Java arrays, which rely on dependent pointer chains. It may be sufficient to extend the “value-safe” concept to array declarations, and allow low-level transformations to change value-safe array declarations from the standard boxed form into an unboxed tuple-based form. Such value-safe arrays would not be convertible to Object[] arrays. Certain connection points, such as Arrays.copyOf and System.arraycopy might need additional input/output combinations, to allow smooth conversion between arrays with boxed and unboxed elements. Alternatively, the correct solution may have to wait until we have enough reification of generic types, and enough operator overloading, to enable an overhaul of Java arrays. Implicit Method Definitions The example of class Complex above may be unattractively complex. I believe most or all of the elements of the example class are required by the logic of value types. If this is true, a programmer who writes a value type will have to write lots of error-prone boilerplate code. On the other hand, I think nearly all of the code (except for the domain-specific parts like plus and minus) can be implicitly generated. Java has a rule for implicitly defining a class’s constructor, if no it defines no constructors explicitly. Likewise, there are rules for providing default access modifiers for interface members. Because of the highly regular structure of value types, it might be reasonable to perform similar implicit transformations on value types. Here’s an example of a “highly implicit” definition of a complex number type: public class Complex implements ValueType { // implicitly final public double re, im; // implicitly public final //implicit methods are defined elementwise from te fields: // toString, asList, equals(2), hashCode, valueOf, cast //optionally, explicit methods (plus, abs, etc.) would go here } In other words, with the right defaults, a simple value type definition can be a one-liner. The observant reader will have noticed the similarities (and suitable differences) between the explicit methods above and the corresponding methods for List<T>. Another way to abbreviate such a class would be to make an annotation the primary trigger of the functionality, and to add the interface(s) implicitly: public @ValueType class Complex { … // implicitly final, implements ValueType (But to me it seems better to communicate the “magic” via an interface, even if it is rooted in an annotation.) Implicitly Defined Value Types So far we have been working with nominal value types, which is to say that the sequence of typed components is associated with a name and additional methods that convey the intention of the programmer. A simple ordered pair of floating point numbers can be variously interpreted as (to name a few possibilities) a rectangular or polar complex number or Cartesian point. The name and the methods convey the intended meaning. But what if we need a truly simple ordered pair of floating point numbers, without any further conceptual baggage? Perhaps we are writing a method (like “divideAndRemainder”) which naturally returns a pair of numbers instead of a single number. Wrapping the pair of numbers in a nominal type (like “QuotientAndRemainder”) makes as little sense as wrapping a single return value in a nominal type (like “Quotient”). What we need here are structural value types commonly known as tuples. For the present discussion, let us assign a conventional, JVM-friendly name to tuples, roughly as follows: public class java.lang.tuple.$DD extends java.lang.tuple.Tuple { double $1, $2; } Here the component names are fixed and all the required methods are defined implicitly. The supertype is an abstract class which has suitable shared declarations. The name itself mentions a JVM-style method parameter descriptor, which may be “cracked” to determine the number and types of the component fields. The odd thing about such a tuple type (and structural types in general) is it must be instantiated lazily, in response to linkage requests from one or more classes that need it. The JVM and/or its class loaders must be prepared to spin a tuple type on demand, given a simple name reference, $xyz, where the xyz is cracked into a series of component types. (Specifics of naming and name mangling need some tasteful engineering.) Tuples also seem to demand, even more than nominal types, some support from the language. (This is probably because notations for non-nominal types work best as combinations of punctuation and type names, rather than named constructors like Function3 or Tuple2.) At a minimum, languages with tuples usually (I think) have some sort of simple bracket notation for creating tuples, and a corresponding pattern-matching syntax (or “destructuring bind”) for taking tuples apart, at least when they are parameter lists. Designing such a syntax is no simple thing, because it ought to play well with nominal value types, and also with pre-existing Java features, such as method parameter lists, implicit conversions, generic types, and reflection. That is a task for another day. Other Use Cases Besides complex numbers and simple tuples there are many use cases for value types. Many tuple-like types have natural value-type representations. These include rational numbers, point locations and pixel colors, and various kinds of dates and addresses. Other types have a variable-length ‘tail’ of internal values. The most common example of this is String, which is (mathematically) a sequence of UTF-16 character values. Similarly, bit vectors, multiple-precision numbers, and polynomials are composed of sequences of values. Such types include, in their representation, a reference to a variable-sized data structure (often an array) which (somehow) represents the sequence of values. The value type may also include ’header’ information. Variable-sized values often have a length distribution which favors short lengths. In that case, the design of the value type can make the first few values in the sequence be direct ’header’ fields of the value type. In the common case where the header is enough to represent the whole value, the tail can be a shared null value, or even just a null reference. Note that the tail need not be an immutable object, as long as the header type encapsulates it well enough. This is the case with String, where the tail is a mutable (but never mutated) character array. Field types and their order must be a globally visible part of the API. The structure of the value type must be transparent enough to have a globally consistent unboxed representation, so that all callers and callees agree about the type and order of components that appear as parameters, return types, and array elements. This is a trade-off between efficiency and encapsulation, which is forced on us when we remove an indirection enjoyed by boxed representations. A JVM-only transformation would not care about such visibility, but a bytecode transformation would need to take care that (say) the components of complex numbers would not get swapped after a redefinition of Complex and a partial recompile. Perhaps constant pool references to value types need to declare the field order as assumed by each API user. This brings up the delicate status of private fields in a value type. It must always be possible to load, store, and copy value types as coordinated groups, and the JVM performs those movements by moving individual scalar values between locals and stack. If a component field is not public, what is to prevent hostile code from plucking it out of the tuple using a rogue aload or astore instruction? Nothing but the verifier, so we may need to give it more smarts, so that it treats value types as inseparable groups of stack slots or locals (something like long or double). My initial thought was to make the fields always public, which would make the security problem moot. But public is not always the right answer; consider the case of String, where the underlying mutable character array must be encapsulated to prevent security holes. I believe we can win back both sides of the tradeoff, by training the verifier never to split up the components in an unboxed value. Just as the verifier encapsulates the two halves of a 64-bit primitive, it can encapsulate the the header and body of an unboxed String, so that no code other than that of class String itself can take apart the values. Similar to String, we could build an efficient multi-precision decimal type along these lines: public final class DecimalValue extends ValueType { protected final long header; protected private final BigInteger digits; public DecimalValue valueOf(int value, int scale) { assert(scale >= 0); return new DecimalValue(((long)value << 32) + scale, null); } public DecimalValue valueOf(long value, int scale) { if (value == (int) value) return valueOf((int)value, scale); return new DecimalValue(-scale, new BigInteger(value)); } } Values of this type would be passed between methods as two machine words. Small values (those with a significand which fits into 32 bits) would be represented without any heap data at all, unless the DecimalValue itself were boxed. (Note the tension between encapsulation and unboxing in this case. It would be better if the header and digits fields were private, but depending on where the unboxing information must “leak”, it is probably safer to make a public revelation of the internal structure.) Note that, although an array of Complex can be faked with a double-length array of double, there is no easy way to fake an array of unboxed DecimalValues. (Either an array of boxed values or a transposed pair of homogeneous arrays would be reasonable fallbacks, in a current JVM.) Getting the full benefit of unboxing and arrays will require some new JVM magic. Although the JVM emphasizes portability, system dependent code will benefit from using machine-level types larger than 64 bits. For example, the back end of a linear algebra package might benefit from value types like Float4 which map to stock vector types. This is probably only worthwhile if the unboxing arrays can be packed with such values. More Daydreams A more finely-divided design for dynamic enforcement of value safety could feature separate marker interfaces for each invariant. An empty marker interface Unsynchronizable could cause suitable exceptions for monitor instructions on objects in marked classes. More radically, a Interchangeable marker interface could cause JVM primitives that are sensitive to object identity to raise exceptions; the strangest result would be that the acmp instruction would have to be specified as raising an exception. @ValueSafe public interface ValueType extends java.io.Serializable, Unsynchronizable, Interchangeable { … public class Complex implements ValueType { // inherits Serializable, Unsynchronizable, Interchangeable, @ValueSafe … It seems possible that Integer and the other wrapper types could be retro-fitted as value-safe types. This is a major change, since wrapper objects would be unsynchronizable and their references interchangeable. It is likely that code which violates value-safety for wrapper types exists but is uncommon. It is less plausible to retro-fit String, since the prominent operation String.intern is often used with value-unsafe code. We should also reconsider the distinction between boxed and unboxed values in code. The design presented above obscures that distinction. As another thought experiment, we could imagine making a first class distinction in the type system between boxed and unboxed representations. Since only primitive types are named with a lower-case initial letter, we could define that the capitalized version of a value type name always refers to the boxed representation, while the initial lower-case variant always refers to boxed. For example: complex pi = complex.valueOf(Math.PI, 0); Complex boxPi = pi; // convert to boxed myList.add(boxPi); complex z = myList.get(0); // unbox Such a convention could perhaps absorb the current difference between int and Integer, double and Double. It might also allow the programmer to express a helpful distinction among array types. As said above, array types are crucial to bulk data interfaces, but are limited in the JVM. Extending arrays beyond the present limitations is worth thinking about; for example, the Maxine JVM implementation has a hybrid object/array type. Something like this which can also accommodate value type components seems worthwhile. On the other hand, does it make sense for value types to contain short arrays? And why should random-access arrays be the end of our design process, when bulk data is often sequentially accessed, and it might make sense to have heterogeneous streams of data as the natural “jumbo” data structure. These considerations must wait for another day and another note. More Work It seems to me that a good sequence for introducing such value types would be as follows: Add the value-safety restrictions to an experimental version of javac. Code some sample applications with value types, including Complex and DecimalValue. Create an experimental JVM which internally unboxes value types but does not require new bytecodes to do so. Ensure the feasibility of the performance model for the sample applications. Add tuple-like bytecodes (with or without generic type reification) to a major revision of the JVM, and teach the Java compiler to switch in the new bytecodes without code changes. A staggered roll-out like this would decouple language changes from bytecode changes, which is always a convenient thing. A similar investigation should be applied (concurrently) to array types. In this case, it seems to me that the starting point is in the JVM: Add an experimental unboxing array data structure to a production JVM, perhaps along the lines of Maxine hybrids. No bytecode or language support is required at first; everything can be done with encapsulated unsafe operations and/or method handles. Create an experimental JVM which internally unboxes value types but does not require new bytecodes to do so. Ensure the feasibility of the performance model for the sample applications. Add tuple-like bytecodes (with or without generic type reification) to a major revision of the JVM, and teach the Java compiler to switch in the new bytecodes without code changes. That’s enough musing me for now. Back to work!

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ANTS CLR and Memory Profiler In Depth Review (Part 1 of 2 – CLR Profiler)

- by ToStringTheory

One of the things that people might not know about me, is my obsession to make my code as efficient as possible. Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind… In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve. One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well. In this review, I am going to cover some of the features of the ANTS profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program. I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction The ANTS Profiler pack provided by Red Gate was something that I had not heard of before receiving an email regarding an offer to review it for a license. Since I look to make my code efficient, it was a no brainer for me to try it out! One thing that I have to say took me by surprise is that upon downloading the program and installing it you fill out a form for your usual contact information. Sure enough within 2 hours, I received an email from a sales representative at Red Gate asking if she could help me to achieve the most out of my trial time so it wouldn’t go to waste. After replying to her and explaining that I was looking to review its feature set, she put me in contact with someone that setup a demo session to give me a quick rundown of its features via an online meeting. After having dealt with a massive ordeal with one of my utility companies and their complete lack of customer service, Red Gates friendly and helpful representatives were a breath of fresh air, and something I was thankful for. ANTS CLR Profiler The ANTS CLR profiler is the thing I want to focus on the most in this post, so I am going to dive right in now. Install was simple and took no time at all. It installed both the profiler for the CLR and Memory, but also visual studio extensions to facilitate the usage of the profilers (click any images for full size images): The Visual Studio menu options (under ANTS menu) Starting the CLR Performance Profiler from the start menu yields this window If you follow the instructions after launching the program from the start menu (Click File > New Profiling Session to start a new project), you are given a dialog with plenty of options for profiling: The New Session dialog. Lots of options. One thing I noticed is that the buttons in the lower right were half-covered by the panel of the application. If I had to guess, I would imagine that this is caused by my DPI settings being set to 125%. This is a problem I have seen in other applications as well that don’t scale well to different dpi scales. The profiler options give you the ability to profile: .NET Executable ASP.NET web application (hosted in IIS) ASP.NET web application (hosted in IIS express) ASP.NET web application (hosted in Cassini Web Development Server) SharePoint web application (hosted in IIS) Silverlight 4+ application Windows Service COM+ server XBAP (local XAML browser application) Attach to an already running .NET 4 process Choosing each option provides a varying set of other variables/options that one can set including options such as application arguments, operating path, record I/O performance performance counters to record (43 counters in all!), etc… All in all, they give you the ability to profile many different .Net project types, and make it simple to do so. In most cases of my using this application, I would be using the built in Visual Studio extensions, as they automatically start a new profiling project in ANTS with the options setup, and start your program, however RedGate has made it easy enough to profile outside of Visual Studio as well. On the flip side of this, as someone who lives most of their work life in Visual Studio, one thing I do wish is that instead of opening an entirely separate application/gui to perform profiling after launching, that instead they would provide a Visual Studio panel with the information, and integrate more of the profiling project information into Visual Studio. So, now that we have an idea of what options that the profiler gives us, its time to test its abilities and features. Horrendous Example Code – Prime Number Generator One of my interests besides development, is Physics and Math – what I went to college for. I have especially always been interested in prime numbers, as they are something of a mystery… So, I decided that I would go ahead and to test the abilities of the profiler, I would write a small program, website, and library to generate prime numbers in the quantity that you ask for. I am going to start off with some terrible code, and show how I would see the profiler being used as a development tool. First off, the IPrimes interface (all code is downloadable at the end of the post): interface IPrimes { IEnumerable<int> GetPrimes(int retrieve); } Simple enough, right? Anything that implements the interface will (hopefully) provide an IEnumerable of int, with the quantity specified in the parameter argument. Next, I am going to implement this interface in the most basic way: public class DumbPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _analyzing = 4; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; //start dividing at 2 //divide until number is reached, or determined not prime for (int i = 2; i < _analyzing && isPrime; i++) { //if (i) goes into _analyzing without a remainder, //_analyzing is NOT prime if (_analyzing % i == 0) isPrime = false; } //if it is prime, add to found list if (isPrime) _foundPrimes.Add(_analyzing); //increment number to analyze next _analyzing++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } This is the simplest way to get primes in my opinion. Checking each number by the straight definition of a prime – is it divisible by anything besides 1 and itself. I have included this code in a base class library for my solution, as I am going to use it to demonstrate a couple of features of ANTS. This class library is consumed by a simple non-MVVM WPF application, and a simple MVC4 website. I will not post the WPF code here inline, as it is simply an ObservableCollection<int>, a label, two textbox’s, and a button. Starting a new Profiling Session So, in Visual Studio, I have just completed my first stint developing the GUI and DumbPrimes IPrimes class, so now I want to check my codes efficiency by profiling it. All I have to do is build the solution (surprised initiating a profiling session doesn’t do this, but I suppose I can understand it), and then click the ANTS menu, followed by Profile Performance. I am then greeted by the profiler starting up and already monitoring my program live: You are provided with a realtime graph at the top, and a pane at the bottom giving you information on how to proceed. I am going to start by asking my program to show me the first 15000 primes: After the program finally began responding again (I did all the work on the main UI thread – how bad!), I stopped the profiler, which did kill the process of my program too. One important thing to note, is that the profiler by default wants to give you a lot of detail about the operation – line hit counts, time per line, percent time per line, etc… The important thing to remember is that this itself takes a lot of time. When running my program without the profiler attached, it can generate the 15000 primes in 5.18 seconds, compared to 74.5 seconds – almost a 1500 percent increase. While this may seem like a lot, remember that there is a trade off. It may be WAY more inefficient, however, I am able to drill down and make improvements to specific problem areas, and then decrease execution time all around. Analyzing the Profiling Session After clicking ‘Stop Profiling’, the process running my application stopped, and the entire execution time was automatically selected by ANTS, and the results shown below: Now there are a number of interesting things going on here, I am going to cover each in a section of its own: Real Time Performance Counter Bar (top of screen) At the top of the screen, is the real time performance bar. As your application is running, this will constantly update with the currently selected performance counters status. A couple of cool things to note are the fact that you can drag a selection around specific time periods to drill down the detail views in the lower 2 panels to information pertaining to only that period. After selecting a time period, you can bookmark a section and name it, so that it is easy to find later, or after reloaded at a later time. You can also zoom in, out, or fit the graph to the space provided – useful for drilling down. It may be hard to see, but at the top of the processor time graph below the time ticks, but above the red usage graph, there is a green bar. This bar shows at what times a method that is selected in the ‘Call tree’ panel is called. Very cool to be able to click on a method and see at what times it made an impact. As I said before, ANTS provides 43 different performance counters you can hook into. Click the arrow next to the Performance tab at the top will allow you to change between different counters if you have them selected: Method Call Tree, ADO.Net Database Calls, File IO – Detail Panel Red Gate really hit the mark here I think. When you select a section of the run with the graph, the call tree populates to fill a hierarchical tree of method calls, with information regarding each of the methods. By default, methods are hidden where the source is not provided (framework type code), however, Red Gate has integrated Reflector into ANTS, so even if you don’t have source for something, you can select a method and get the source if you want. Methods are also hidden where the impact is seen as insignificant – methods that are only executed for 1% of the time of the overall calling methods time; in other words, working on making them better is not where your efforts should be focused. – Smart! Source Panel – Detail Panel The source panel is where you can see line level information on your code, showing the code for the currently selected method from the Method Call Tree. If the code is not available, Reflector takes care of it and shows the code anyways! As you can notice, there does seem to be a problem with how ANTS determines what line is the actual line that a call is completed on. I have suspicions that this may be due to some of the inline code optimizations that the CLR applies upon compilation of the assembly. In a method with comments, the problem is much more severe: As you can see here, apparently the most offending code in my base library was a comment – *gasp*! Removing the comments does help quite a bit, however I hope that Red Gate works on their counter algorithm soon to improve the logic on positioning for statistics: I did a small test just to demonstrate the lines are correct without comments. For me, it isn’t a deal breaker, as I can usually determine the correct placements by looking at the application code in the region and determining what makes sense, but it is something that would probably build up some irritation with time. Feature – Suggest Method for Optimization A neat feature to really help those in need of a pointer, is the menu option under tools to automatically suggest methods to optimize/improve: Nice feature – clicking it filters the call tree and stars methods that it thinks are good candidates for optimization. I do wish that they would have made it more visible for those of use who aren’t great on sight: Process Integration I do think that this could have a place in my process. After experimenting with the profiler, I do think it would be a great benefit to do some development, testing, and then after all the bugs are worked out, use the profiler to check on things to make sure nothing seems like it is hogging more than its fair share. For example, with this program, I would have developed it, ran it, tested it – it works, but slowly. After looking at the profiler, and seeing the massive amount of time spent in 1 method, I might go ahead and try to re-implement IPrimes (I actually would probably rewrite the offending code, but so that I can distribute both sets of code easily, I’m just going to make another implementation of IPrimes). Using two pieces of knowledge about prime numbers can make this method MUCH more efficient – prime numbers fall into two buckets 6k+/-1 , and a number is prime if it is not divisible by any other primes before it: public class SmartPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _k = 1; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; int potentialPrime; //analyze 6k-1 //assign the value to potential potentialPrime = 6 * _k - 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); if (_foundPrimes.Count() == retrieve) break; //analyze 6k+1 //assign the value to potential potentialPrime = 6 * _k + 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); //increment k to analyze next _k++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } Now there are definitely more things I can do to help make this more efficient, but for the scope of this example, I think this is fine (but still hideous)! Profiling this now yields a happy surprise 27 seconds to generate the 15000 primes with the profiler attached, and only 1.43 seconds without. One important thing I wanted to call out though was the performance graph now: Notice anything odd? The %Processor time is above 100%. This is because there is now more than 1 core in the operation. A better label for the chart in my mind would have been %Core time, but to each their own. Another odd thing I noticed was that the profiler seemed to be spot on this time in my DumbPrimes class with line details in source, even with comments.. Odd. Profiling Web Applications The last thing that I wanted to cover, that means a lot to me as a web developer, is the great amount of work that Red Gate put into the profiler when profiling web applications. In my solution, I have a simple MVC4 application setup with 1 page, a single input form, that will output prime values as my WPF app did. Launching the profiler from Visual Studio as before, nothing is really different in the profiler window, however I did receive a UAC prompt for a Red Gate helper app to integrate with the web server without notification. After requesting 500, 1000, 2000, and 5000 primes, and looking at the profiler session, things are slightly different from before: As you can see, there are 4 spikes of activity in the processor time graph, but there is also something new in the call tree: That’s right – ANTS will actually group method calls by get/post operations, so it is easier to find out what action/page is giving the largest problems… Pretty cool in my mind! Overview Overall, I think that Red Gate ANTS CLR Profiler has a lot to offer, however I think it also has a long ways to go. 3 Biggest Pros: Ability to easily drill down from time graph, to method calls, to source code Wide variety of counters to choose from when profiling your application Excellent integration/grouping of methods being called from web applications by request – BRILLIANT! 3 Biggest Cons: Issue regarding line details in source view Nit pick – Processor time vs. Core time Nit pick – Lack of full integration with Visual Studio Ratings Ease of Use (7/10) – I marked down here because of the problems with the line level details and the extra work that that entails, and the lack of better integration with Visual Studio. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do. Especially with its large variety of performance counters, a definite plus! Features (9/10) – Besides the real time performance monitoring, and the drill downs that I’ve shown here, ANTS also has great integration with ADO.Net, with the ability to show database queries run by your application in the profiler. This, with the line level details, the web request grouping, reflector integration, and various options to customize your profiling session I think create a great set of features! Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good. their people are friendly, helpful, and happy! UI / UX (8/10) – The interface is very easy to get around, and all of the options are easy to find. With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (8/10) – Overall, I am happy with the Performance Profiler and its features, as well as with the service I received when working with the Red Gate personnel. I WOULD recommend you trying the application and seeing if it would fit into your process, BUT, remember there are still some kinks in it to hopefully be worked out. My next post will definitely be shorter (hopefully), but thank you for reading up to here, or skipping ahead! Please, if you do try the product, drop me a message and let me know what you think! I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

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Metro: Creating an IndexedDbDataSource for WinJS

- by Stephen.Walther

The goal of this blog entry is to describe how you can create custom data sources which you can use with the controls in the WinJS library. In particular, I explain how you can create an IndexedDbDataSource which you can use to store and retrieve data from an IndexedDB database. If you want to skip ahead, and ignore all of the fascinating content in-between, I’ve included the complete code for the IndexedDbDataSource at the very bottom of this blog entry. What is IndexedDB? IndexedDB is a database in the browser. You can use the IndexedDB API with all modern browsers including Firefox, Chrome, and Internet Explorer 10. And, of course, you can use IndexedDB with Metro style apps written with JavaScript. If you need to persist data in a Metro style app written with JavaScript then IndexedDB is a good option. Each Metro app can only interact with its own IndexedDB databases. And, IndexedDB provides you with transactions, indices, and cursors – the elements of any modern database. An IndexedDB database might be different than the type of database that you normally use. An IndexedDB database is an object-oriented database and not a relational database. Instead of storing data in tables, you store data in object stores. You store JavaScript objects in an IndexedDB object store. You create new IndexedDB object stores by handling the upgradeneeded event when you attempt to open a connection to an IndexedDB database. For example, here’s how you would both open a connection to an existing database named TasksDB and create the TasksDB database when it does not already exist: var reqOpen = window.indexedDB.open(“TasksDB”, 2); reqOpen.onupgradeneeded = function (evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); }; reqOpen.onsuccess = function () { var db = reqOpen.result; // Do something with db }; When you call window.indexedDB.open(), and the database does not already exist, then the upgradeneeded event is raised. In the code above, the upgradeneeded handler creates a new object store named tasks. The new object store has an auto-increment column named id which acts as the primary key column. If the database already exists with the right version, and you call window.indexedDB.open(), then the success event is raised. At that point, you have an open connection to the existing database and you can start doing something with the database. You use asynchronous methods to interact with an IndexedDB database. For example, the following code illustrates how you would add a new object to the tasks object store: var transaction = db.transaction(“tasks”, “readwrite”); var reqAdd = transaction.objectStore(“tasks”).add({ name: “Feed the dog” }); reqAdd.onsuccess = function() { // Tasks added successfully }; The code above creates a new database transaction, adds a new task to the tasks object store, and handles the success event. If the new task gets added successfully then the success event is raised. Creating a WinJS IndexedDbDataSource The most powerful control in the WinJS library is the ListView control. This is the control that you use to display a collection of items. If you want to display data with a ListView control, you need to bind the control to a data source. The WinJS library includes two objects which you can use as a data source: the List object and the StorageDataSource object. The List object enables you to represent a JavaScript array as a data source and the StorageDataSource enables you to represent the file system as a data source. If you want to bind an IndexedDB database to a ListView then you have a choice. You can either dump the items from the IndexedDB database into a List object or you can create a custom data source. I explored the first approach in a previous blog entry. In this blog entry, I explain how you can create a custom IndexedDB data source. Implementing the IListDataSource Interface You create a custom data source by implementing the IListDataSource interface. This interface contains the contract for the methods which the ListView needs to interact with a data source. The easiest way to implement the IListDataSource interface is to derive a new object from the base VirtualizedDataSource object. The VirtualizedDataSource object requires a data adapter which implements the IListDataAdapter interface. Yes, because of the number of objects involved, this is a little confusing. Your code ends up looking something like this: var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); The code above is used to create a new class named IndexedDbDataSource which derives from the base VirtualizedDataSource class. In the constructor for the new class, the base class _baseDataSourceConstructor() method is called. A data adapter is passed to the _baseDataSourceConstructor() method. The code above creates a new method exposed by the IndexedDbDataSource named nuke(). The nuke() method deletes all of the objects from an object store. The code above also overrides a method named remove(). Our derived remove() method accepts any type of key and removes the matching item from the object store. Almost all of the work of creating a custom data source goes into building the data adapter class. The data adapter class implements the IListDataAdapter interface which contains the following methods: · change() · getCount() · insertAfter() · insertAtEnd() · insertAtStart() · insertBefore() · itemsFromDescription() · itemsFromEnd() · itemsFromIndex() · itemsFromKey() · itemsFromStart() · itemSignature() · moveAfter() · moveBefore() · moveToEnd() · moveToStart() · remove() · setNotificationHandler() · compareByIdentity Fortunately, you are not required to implement all of these methods. You only need to implement the methods that you actually need. In the case of the IndexedDbDataSource, I implemented the getCount(), itemsFromIndex(), insertAtEnd(), and remove() methods. If you are creating a read-only data source then you really only need to implement the getCount() and itemsFromIndex() methods. Implementing the getCount() Method The getCount() method returns the total number of items from the data source. So, if you are storing 10,000 items in an object store then this method would return the value 10,000. Here’s how I implemented the getCount() method: getCount: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore().then(function (store) { var reqCount = store.count(); reqCount.onerror = that._error; reqCount.onsuccess = function (evt) { complete(evt.target.result); }; }); }); } The first thing that you should notice is that the getCount() method returns a WinJS promise. This is a requirement. The getCount() method is asynchronous which is a good thing because all of the IndexedDB methods (at least the methods implemented in current browsers) are also asynchronous. The code above retrieves an object store and then uses the IndexedDB count() method to get a count of the items in the object store. The value is returned from the promise by calling complete(). Implementing the itemsFromIndex method When a ListView displays its items, it calls the itemsFromIndex() method. By default, it calls this method multiple times to get different ranges of items. Three parameters are passed to the itemsFromIndex() method: the requestIndex, countBefore, and countAfter parameters. The requestIndex indicates the index of the item from the database to show. The countBefore and countAfter parameters represent hints. These are integer values which represent the number of items before and after the requestIndex to retrieve. Again, these are only hints and you can return as many items before and after the request index as you please. Here’s how I implemented the itemsFromIndex method: itemsFromIndex: function (requestIndex, countBefore, countAfter) { var that = this; return new WinJS.Promise(function (complete, error) { that.getCount().then(function (count) { if (requestIndex >= count) { return WinJS.Promise.wrapError(new WinJS.ErrorFromName(WinJS.UI.FetchError.doesNotExist)); } var startIndex = Math.max(0, requestIndex - countBefore); var endIndex = Math.min(count, requestIndex + countAfter + 1); that._getObjectStore().then(function (store) { var index = 0; var items = []; var req = store.openCursor(); req.onerror = that._error; req.onsuccess = function (evt) { var cursor = evt.target.result; if (index < startIndex) { index = startIndex; cursor.advance(startIndex); return; } if (cursor && index < endIndex) { index++; items.push({ key: cursor.value[store.keyPath].toString(), data: cursor.value }); cursor.continue(); return; } results = { items: items, offset: requestIndex - startIndex, totalCount: count }; complete(results); }; }); }); }); } In the code above, a cursor is used to iterate through the objects in an object store. You fetch the next item in the cursor by calling either the cursor.continue() or cursor.advance() method. The continue() method moves forward by one object and the advance() method moves forward a specified number of objects. Each time you call continue() or advance(), the success event is raised again. If the cursor is null then you know that you have reached the end of the cursor and you can return the results. Some things to be careful about here. First, the return value from the itemsFromIndex() method must implement the IFetchResult interface. In particular, you must return an object which has an items, offset, and totalCount property. Second, each item in the items array must implement the IListItem interface. Each item should have a key and a data property. Implementing the insertAtEnd() Method When creating the IndexedDbDataSource, I wanted to go beyond creating a simple read-only data source and support inserting and deleting objects. If you want to support adding new items with your data source then you need to implement the insertAtEnd() method. Here’s how I implemented the insertAtEnd() method for the IndexedDbDataSource: insertAtEnd:function(unused, data) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function(store) { var reqAdd = store.add(data); reqAdd.onerror = that._error; reqAdd.onsuccess = function (evt) { var reqGet = store.get(evt.target.result); reqGet.onerror = that._error; reqGet.onsuccess = function (evt) { var newItem = { key:evt.target.result[store.keyPath].toString(), data:evt.target.result } complete(newItem); }; }; }); }); } When implementing the insertAtEnd() method, you need to be careful to return an object which implements the IItem interface. In particular, you should return an object that has a key and a data property. The key must be a string and it uniquely represents the new item added to the data source. The value of the data property represents the new item itself. Implementing the remove() Method Finally, you use the remove() method to remove an item from the data source. You call the remove() method with the key of the item which you want to remove. Implementing the remove() method in the case of the IndexedDbDataSource was a little tricky. The problem is that an IndexedDB object store uses an integer key and the VirtualizedDataSource requires a string key. For that reason, I needed to override the remove() method in the derived IndexedDbDataSource class like this: var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); When you call remove(), you end up calling a method of the IndexedDbDataAdapter named removeInternal() . Here’s what the removeInternal() method looks like: setNotificationHandler: function (notificationHandler) { this._notificationHandler = notificationHandler; }, removeInternal: function(key) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqDelete = store.delete (key); reqDelete.onerror = that._error; reqDelete.onsuccess = function (evt) { that._notificationHandler.removed(key.toString()); complete(); }; }); }); } The removeInternal() method calls the IndexedDB delete() method to delete an item from the object store. If the item is deleted successfully then the _notificationHandler.remove() method is called. Because we are not implementing the standard IListDataAdapter remove() method, we need to notify the data source (and the ListView control bound to the data source) that an item has been removed. The way that you notify the data source is by calling the _notificationHandler.remove() method. Notice that we get the _notificationHandler in the code above by implementing another method in the IListDataAdapter interface: the setNotificationHandler() method. You can raise the following types of notifications using the _notificationHandler: · beginNotifications() · changed() · endNotifications() · inserted() · invalidateAll() · moved() · removed() · reload() These methods are all part of the IListDataNotificationHandler interface in the WinJS library. Implementing the nuke() Method I wanted to implement a method which would remove all of the items from an object store. Therefore, I created a method named nuke() which calls the IndexedDB clear() method: nuke: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqClear = store.clear(); reqClear.onerror = that._error; reqClear.onsuccess = function (evt) { that._notificationHandler.reload(); complete(); }; }); }); } Notice that the nuke() method calls the _notificationHandler.reload() method to notify the ListView to reload all of the items from its data source. Because we are implementing a custom method here, we need to use the _notificationHandler to send an update. Using the IndexedDbDataSource To illustrate how you can use the IndexedDbDataSource, I created a simple task list app. You can add new tasks, delete existing tasks, and nuke all of the tasks. You delete an item by selecting an item (swipe or right-click) and clicking the Delete button. Here’s the HTML page which contains the ListView, the form for adding new tasks, and the buttons for deleting and nuking tasks: <!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title>DataSources</title>  <link href="//Microsoft.WinJS.1.0.RC/css/ui-dark.css" rel="stylesheet" /> <script src="//Microsoft.WinJS.1.0.RC/js/base.js"></script> <script src="//Microsoft.WinJS.1.0.RC/js/ui.js"></script>  <link href="indexedDb.css" rel="stylesheet" /> <script type="text/javascript" src="indexedDbDataSource.js"></script> <script src="indexedDb.js"></script> </head> <body> <div id="tmplTask" data-win-control="WinJS.Binding.Template"> <div class="taskItem"> Id: <span data-win-bind="innerText:id"></span> <br /><br /> Name: <span data-win-bind="innerText:name"></span> </div> </div> <div id="lvTasks" data-win-control="WinJS.UI.ListView" data-win-options="{ itemTemplate: select('#tmplTask'), selectionMode: 'single' }"></div> <form id="frmAdd"> <fieldset> <legend>Add Task</legend> <label>New Task</label> <input id="inputTaskName" required /> <button>Add</button> </fieldset> </form> <button id="btnNuke">Nuke</button> <button id="btnDelete">Delete</button> </body> </html> And here is the JavaScript code for the TaskList app: /// <reference path="//Microsoft.WinJS.1.0.RC/js/base.js" /> /// <reference path="//Microsoft.WinJS.1.0.RC/js/ui.js" /> function init() { WinJS.UI.processAll().done(function () { var lvTasks = document.getElementById("lvTasks").winControl; // Bind the ListView to its data source var tasksDataSource = new DataSources.IndexedDbDataSource("TasksDB", 1, "tasks", upgrade); lvTasks.itemDataSource = tasksDataSource; // Wire-up Add, Delete, Nuke buttons document.getElementById("frmAdd").addEventListener("submit", function (evt) { evt.preventDefault(); tasksDataSource.beginEdits(); tasksDataSource.insertAtEnd(null, { name: document.getElementById("inputTaskName").value }).done(function (newItem) { tasksDataSource.endEdits(); document.getElementById("frmAdd").reset(); lvTasks.ensureVisible(newItem.index); }); }); document.getElementById("btnDelete").addEventListener("click", function () { if (lvTasks.selection.count() == 1) { lvTasks.selection.getItems().done(function (items) { tasksDataSource.remove(items[0].data.id); }); } }); document.getElementById("btnNuke").addEventListener("click", function () { tasksDataSource.nuke(); }); // This method is called to initialize the IndexedDb database function upgrade(evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); } }); } document.addEventListener("DOMContentLoaded", init); The IndexedDbDataSource is created and bound to the ListView control with the following two lines of code: var tasksDataSource = new DataSources.IndexedDbDataSource("TasksDB", 1, "tasks", upgrade); lvTasks.itemDataSource = tasksDataSource; The IndexedDbDataSource is created with four parameters: the name of the database to create, the version of the database to create, the name of the object store to create, and a function which contains code to initialize the new database. The upgrade function creates a new object store named tasks with an auto-increment property named id: function upgrade(evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); } The Complete Code for the IndexedDbDataSource Here’s the complete code for the IndexedDbDataSource: (function () { /************************************************ * The IndexedDBDataAdapter enables you to work * with a HTML5 IndexedDB database. *************************************************/ var IndexedDbDataAdapter = WinJS.Class.define( function (dbName, dbVersion, objectStoreName, upgrade, error) { this._dbName = dbName; // database name this._dbVersion = dbVersion; // database version this._objectStoreName = objectStoreName; // object store name this._upgrade = upgrade; // database upgrade script this._error = error || function (evt) { console.log(evt.message); }; }, { /******************************************* * IListDataAdapter Interface Methods ********************************************/ getCount: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore().then(function (store) { var reqCount = store.count(); reqCount.onerror = that._error; reqCount.onsuccess = function (evt) { complete(evt.target.result); }; }); }); }, itemsFromIndex: function (requestIndex, countBefore, countAfter) { var that = this; return new WinJS.Promise(function (complete, error) { that.getCount().then(function (count) { if (requestIndex >= count) { return WinJS.Promise.wrapError(new WinJS.ErrorFromName(WinJS.UI.FetchError.doesNotExist)); } var startIndex = Math.max(0, requestIndex - countBefore); var endIndex = Math.min(count, requestIndex + countAfter + 1); that._getObjectStore().then(function (store) { var index = 0; var items = []; var req = store.openCursor(); req.onerror = that._error; req.onsuccess = function (evt) { var cursor = evt.target.result; if (index < startIndex) { index = startIndex; cursor.advance(startIndex); return; } if (cursor && index < endIndex) { index++; items.push({ key: cursor.value[store.keyPath].toString(), data: cursor.value }); cursor.continue(); return; } results = { items: items, offset: requestIndex - startIndex, totalCount: count }; complete(results); }; }); }); }); }, insertAtEnd:function(unused, data) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function(store) { var reqAdd = store.add(data); reqAdd.onerror = that._error; reqAdd.onsuccess = function (evt) { var reqGet = store.get(evt.target.result); reqGet.onerror = that._error; reqGet.onsuccess = function (evt) { var newItem = { key:evt.target.result[store.keyPath].toString(), data:evt.target.result } complete(newItem); }; }; }); }); }, setNotificationHandler: function (notificationHandler) { this._notificationHandler = notificationHandler; }, /***************************************** * IndexedDbDataSource Method ******************************************/ removeInternal: function(key) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqDelete = store.delete (key); reqDelete.onerror = that._error; reqDelete.onsuccess = function (evt) { that._notificationHandler.removed(key.toString()); complete(); }; }); }); }, nuke: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqClear = store.clear(); reqClear.onerror = that._error; reqClear.onsuccess = function (evt) { that._notificationHandler.reload(); complete(); }; }); }); }, /******************************************* * Private Methods ********************************************/ _ensureDbOpen: function () { var that = this; // Try to get cached Db if (that._cachedDb) { return WinJS.Promise.wrap(that._cachedDb); } // Otherwise, open the database return new WinJS.Promise(function (complete, error, progress) { var reqOpen = window.indexedDB.open(that._dbName, that._dbVersion); reqOpen.onerror = function (evt) { error(); }; reqOpen.onupgradeneeded = function (evt) { that._upgrade(evt); that._notificationHandler.invalidateAll(); }; reqOpen.onsuccess = function () { that._cachedDb = reqOpen.result; complete(that._cachedDb); }; }); }, _getObjectStore: function (type) { type = type || "readonly"; var that = this; return new WinJS.Promise(function (complete, error) { that._ensureDbOpen().then(function (db) { var transaction = db.transaction(that._objectStoreName, type); complete(transaction.objectStore(that._objectStoreName)); }); }); }, _get: function (key) { return new WinJS.Promise(function (complete, error) { that._getObjectStore().done(function (store) { var reqGet = store.get(key); reqGet.onerror = that._error; reqGet.onsuccess = function (item) { complete(item); }; }); }); } } ); var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); WinJS.Namespace.define("DataSources", { IndexedDbDataSource: IndexedDbDataSource }); })(); Summary In this blog post, I provided an overview of how you can create a new data source which you can use with the WinJS library. I described how you can create an IndexedDbDataSource which you can use to bind a ListView control to an IndexedDB database. While describing how you can create a custom data source, I explained how you can implement the IListDataAdapter interface. You also learned how to raise notifications — such as a removed or invalidateAll notification — by taking advantage of the methods of the IListDataNotificationHandler interface.

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256 Windows Azure Worker Roles, Windows Kinect and a 90's Text-Based Ray-Tracer

- by Alan Smith

For a couple of years I have been demoing a simple render farm hosted in Windows Azure using worker roles and the Azure Storage service. At the start of the presentation I deploy an Azure application that uses 16 worker roles to render a 1,500 frame 3D ray-traced animation. At the end of the presentation, when the animation was complete, I would play the animation delete the Azure deployment. The standing joke with the audience was that it was that it was a “$2 demo”, as the compute charges for running the 16 instances for an hour was $1.92, factor in the bandwidth charges and it’s a couple of dollars. The point of the demo is that it highlights one of the great benefits of cloud computing, you pay for what you use, and if you need massive compute power for a short period of time using Windows Azure can work out very cost effective. The “$2 demo” was great for presenting at user groups and conferences in that it could be deployed to Azure, used to render an animation, and then removed in a one hour session. I have always had the idea of doing something a bit more impressive with the demo, and scaling it from a “$2 demo” to a “$30 demo”. The challenge was to create a visually appealing animation in high definition format and keep the demo time down to one hour. This article will take a run through how I achieved this. Ray Tracing Ray tracing, a technique for generating high quality photorealistic images, gained popularity in the 90’s with companies like Pixar creating feature length computer animations, and also the emergence of shareware text-based ray tracers that could run on a home PC. In order to render a ray traced image, the ray of light that would pass from the view point must be tracked until it intersects with an object. At the intersection, the color, reflectiveness, transparency, and refractive index of the object are used to calculate if the ray will be reflected or refracted. Each pixel may require thousands of calculations to determine what color it will be in the rendered image. Pin-Board Toys Having very little artistic talent and a basic understanding of maths I decided to focus on an animation that could be modeled fairly easily and would look visually impressive. I’ve always liked the pin-board desktop toys that become popular in the 80’s and when I was working as a 3D animator back in the 90’s I always had the idea of creating a 3D ray-traced animation of a pin-board, but never found the energy to do it. Even if I had a go at it, the render time to produce an animation that would look respectable on a 486 would have been measured in months. PolyRay Back in 1995 I landed my first real job, after spending three years being a beach-ski-climbing-paragliding-bum, and was employed to create 3D ray-traced animations for a CD-ROM that school kids would use to learn physics. I had got into the strange and wonderful world of text-based ray tracing, and was using a shareware ray-tracer called PolyRay. PolyRay takes a text file describing a scene as input and, after a few hours processing on a 486, produced a high quality ray-traced image. The following is an example of a basic PolyRay scene file. background Midnight_Blue static define matte surface { ambient 0.1 diffuse 0.7 } define matte_white texture { matte { color white } } define matte_black texture { matte { color dark_slate_gray } } define position_cylindrical 3 define lookup_sawtooth 1 define light_wood <0.6, 0.24, 0.1> define median_wood <0.3, 0.12, 0.03> define dark_wood <0.05, 0.01, 0.005> define wooden texture { noise surface { ambient 0.2 diffuse 0.7 specular white, 0.5 microfacet Reitz 10 position_fn position_cylindrical position_scale 1 lookup_fn lookup_sawtooth octaves 1 turbulence 1 color_map( [0.0, 0.2, light_wood, light_wood] [0.2, 0.3, light_wood, median_wood] [0.3, 0.4, median_wood, light_wood] [0.4, 0.7, light_wood, light_wood] [0.7, 0.8, light_wood, median_wood] [0.8, 0.9, median_wood, light_wood] [0.9, 1.0, light_wood, dark_wood]) } } define glass texture { surface { ambient 0 diffuse 0 specular 0.2 reflection white, 0.1 transmission white, 1, 1.5 }} define shiny surface { ambient 0.1 diffuse 0.6 specular white, 0.6 microfacet Phong 7 } define steely_blue texture { shiny { color black } } define chrome texture { surface { color white ambient 0.0 diffuse 0.2 specular 0.4 microfacet Phong 10 reflection 0.8 } } viewpoint { from <4.000, -1.000, 1.000> at <0.000, 0.000, 0.000> up <0, 1, 0> angle 60 resolution 640, 480 aspect 1.6 image_format 0 } light <-10, 30, 20> light <-10, 30, -20> object { disc <0, -2, 0>, <0, 1, 0>, 30 wooden } object { sphere <0.000, 0.000, 0.000>, 1.00 chrome } object { cylinder <0.000, 0.000, 0.000>, <0.000, 0.000, -4.000>, 0.50 chrome } After setting up the background and defining colors and textures, the viewpoint is specified. The “camera” is located at a point in 3D space, and it looks towards another point. The angle, image resolution, and aspect ratio are specified. Two lights are present in the image at defined coordinates. The three objects in the image are a wooden disc to represent a table top, and a sphere and cylinder that intersect to form a pin that will be used for the pin board toy in the final animation. When the image is rendered, the following image is produced. The pins are modeled with a chrome surface, so they reflect the environment around them. Note that the scale of the pin shaft is not correct, this will be fixed later. Modeling the Pin Board The frame of the pin-board is made up of three boxes, and six cylinders, the front box is modeled using a clear, slightly reflective solid, with the same refractive index of glass. The other shapes are modeled as metal. object { box <-5.5, -1.5, 1>, <5.5, 5.5, 1.2> glass } object { box <-5.5, -1.5, -0.04>, <5.5, 5.5, -0.09> steely_blue } object { box <-5.5, -1.5, -0.52>, <5.5, 5.5, -0.59> steely_blue } object { cylinder <-5.2, -1.2, 1.4>, <-5.2, -1.2, -0.74>, 0.2 steely_blue } object { cylinder <5.2, -1.2, 1.4>, <5.2, -1.2, -0.74>, 0.2 steely_blue } object { cylinder <-5.2, 5.2, 1.4>, <-5.2, 5.2, -0.74>, 0.2 steely_blue } object { cylinder <5.2, 5.2, 1.4>, <5.2, 5.2, -0.74>, 0.2 steely_blue } object { cylinder <0, -1.2, 1.4>, <0, -1.2, -0.74>, 0.2 steely_blue } object { cylinder <0, 5.2, 1.4>, <0, 5.2, -0.74>, 0.2 steely_blue } In order to create the matrix of pins that make up the pin board I used a basic console application with a few nested loops to create two intersecting matrixes of pins, which models the layout used in the pin boards. The resulting image is shown below. The pin board contains 11,481 pins, with the scene file containing 23,709 lines of code. For the complete animation 2,000 scene files will be created, which is over 47 million lines of code. Each pin in the pin-board will slide out a specific distance when an object is pressed into the back of the board. This is easily modeled by setting the Z coordinate of the pin to a specific value. In order to set all of the pins in the pin-board to the correct position, a bitmap image can be used. The position of the pin can be set based on the color of the pixel at the appropriate position in the image. When the Windows Azure logo is used to set the Z coordinate of the pins, the following image is generated. The challenge now was to make a cool animation. The Azure Logo is fine, but it is static. Using a normal video to animate the pins would not work; the colors in the video would not be the same as the depth of the objects from the camera. In order to simulate the pin board accurately a series of frames from a depth camera could be used. Windows Kinect The Kenect controllers for the X-Box 360 and Windows feature a depth camera. The Kinect SDK for Windows provides a programming interface for Kenect, providing easy access for .NET developers to the Kinect sensors. The Kinect Explorer provided with the Kinect SDK is a great starting point for exploring Kinect from a developers perspective. Both the X-Box 360 Kinect and the Windows Kinect will work with the Kinect SDK, the Windows Kinect is required for commercial applications, but the X-Box Kinect can be used for hobby projects. The Windows Kinect has the advantage of providing a mode to allow depth capture with objects closer to the camera, which makes for a more accurate depth image for setting the pin positions. Creating a Depth Field Animation The depth field animation used to set the positions of the pin in the pin board was created using a modified version of the Kinect Explorer sample application. In order to simulate the pin board accurately, a small section of the depth range from the depth sensor will be used. Any part of the object in front of the depth range will result in a white pixel; anything behind the depth range will be black. Within the depth range the pixels in the image will be set to RGB values from 0,0,0 to 255,255,255. A screen shot of the modified Kinect Explorer application is shown below. The Kinect Explorer sample application was modified to include slider controls that are used to set the depth range that forms the image from the depth stream. This allows the fine tuning of the depth image that is required for simulating the position of the pins in the pin board. The Kinect Explorer was also modified to record a series of images from the depth camera and save them as a sequence JPEG files that will be used to animate the pins in the animation the Start and Stop buttons are used to start and stop the image recording. En example of one of the depth images is shown below. Once a series of 2,000 depth images has been captured, the task of creating the animation can begin. Rendering a Test Frame In order to test the creation of frames and get an approximation of the time required to render each frame a test frame was rendered on-premise using PolyRay. The output of the rendering process is shown below. The test frame contained 23,629 primitive shapes, most of which are the spheres and cylinders that are used for the 11,800 or so pins in the pin board. The 1280x720 image contains 921,600 pixels, but as anti-aliasing was used the number of rays that were calculated was 4,235,777, with 3,478,754,073 object boundaries checked. The test frame of the pin board with the depth field image applied is shown below. The tracing time for the test frame was 4 minutes 27 seconds, which means rendering the2,000 frames in the animation would take over 148 hours, or a little over 6 days. Although this is much faster that an old 486, waiting almost a week to see the results of an animation would make it challenging for animators to create, view, and refine their animations. It would be much better if the animation could be rendered in less than one hour. Windows Azure Worker Roles The cost of creating an on-premise render farm to render animations increases in proportion to the number of servers. The table below shows the cost of servers for creating a render farm, assuming a cost of $500 per server. Number of Servers Cost 1 $500 16 $8,000 256 $128,000 As well as the cost of the servers, there would be additional costs for networking, racks etc. Hosting an environment of 256 servers on-premise would require a server room with cooling, and some pretty hefty power cabling. The Windows Azure compute services provide worker roles, which are ideal for performing processor intensive compute tasks. With the scalability available in Windows Azure a job that takes 256 hours to complete could be perfumed using different numbers of worker roles. The time and cost of using 1, 16 or 256 worker roles is shown below. Number of Worker Roles Render Time Cost 1 256 hours $30.72 16 16 hours $30.72 256 1 hour $30.72 Using worker roles in Windows Azure provides the same cost for the 256 hour job, irrespective of the number of worker roles used. Provided the compute task can be broken down into many small units, and the worker role compute power can be used effectively, it makes sense to scale the application so that the task is completed quickly, making the results available in a timely fashion. The task of rendering 2,000 frames in an animation is one that can easily be broken down into 2,000 individual pieces, which can be performed by a number of worker roles. Creating a Render Farm in Windows Azure The architecture of the render farm is shown in the following diagram. The render farm is a hybrid application with the following components: · On-Premise o Windows Kinect – Used combined with the Kinect Explorer to create a stream of depth images. o Animation Creator – This application uses the depth images from the Kinect sensor to create scene description files for PolyRay. These files are then uploaded to the jobs blob container, and job messages added to the jobs queue. o Process Monitor – This application queries the role instance lifecycle table and displays statistics about the render farm environment and render process. o Image Downloader – This application polls the image queue and downloads the rendered animation files once they are complete. · Windows Azure o Azure Storage – Queues and blobs are used for the scene description files and completed frames. A table is used to store the statistics about the rendering environment. The architecture of each worker role is shown below. The worker role is configured to use local storage, which provides file storage on the worker role instance that can be use by the applications to render the image and transform the format of the image. The service definition for the worker role with the local storage configuration highlighted is shown below. <?xml version="1.0" encoding="utf-8"?> <ServiceDefinition name="CloudRay" > <WorkerRole name="CloudRayWorkerRole" vmsize="Small"> <Imports> </Imports> <ConfigurationSettings> <Setting name="DataConnectionString" /> </ConfigurationSettings> <LocalResources> <LocalStorage name="RayFolder" cleanOnRoleRecycle="true" /> </LocalResources> </WorkerRole> </ServiceDefinition> The two executable programs, PolyRay.exe and DTA.exe are included in the Azure project, with Copy Always set as the property. PolyRay will take the scene description file and render it to a Truevision TGA file. As the TGA format has not seen much use since the mid 90’s it is converted to a JPG image using Dave's Targa Animator, another shareware application from the 90’s. Each worker roll will use the following process to render the animation frames. 1. The worker process polls the job queue, if a job is available the scene description file is downloaded from blob storage to local storage. 2. PolyRay.exe is started in a process with the appropriate command line arguments to render the image as a TGA file. 3. DTA.exe is started in a process with the appropriate command line arguments convert the TGA file to a JPG file. 4. The JPG file is uploaded from local storage to the images blob container. 5. A message is placed on the images queue to indicate a new image is available for download. 6. The job message is deleted from the job queue. 7. The role instance lifecycle table is updated with statistics on the number of frames rendered by the worker role instance, and the CPU time used. The code for this is shown below. public override void Run() { // Set environment variables string polyRayPath = Path.Combine(Environment.GetEnvironmentVariable("RoleRoot"), PolyRayLocation); string dtaPath = Path.Combine(Environment.GetEnvironmentVariable("RoleRoot"), DTALocation); LocalResource rayStorage = RoleEnvironment.GetLocalResource("RayFolder"); string localStorageRootPath = rayStorage.RootPath; JobQueue jobQueue = new JobQueue("renderjobs"); JobQueue downloadQueue = new JobQueue("renderimagedownloadjobs"); CloudRayBlob sceneBlob = new CloudRayBlob("scenes"); CloudRayBlob imageBlob = new CloudRayBlob("images"); RoleLifecycleDataSource roleLifecycleDataSource = new RoleLifecycleDataSource(); Frames = 0; while (true) { // Get the render job from the queue CloudQueueMessage jobMsg = jobQueue.Get(); if (jobMsg != null) { // Get the file details string sceneFile = jobMsg.AsString; string tgaFile = sceneFile.Replace(".pi", ".tga"); string jpgFile = sceneFile.Replace(".pi", ".jpg"); string sceneFilePath = Path.Combine(localStorageRootPath, sceneFile); string tgaFilePath = Path.Combine(localStorageRootPath, tgaFile); string jpgFilePath = Path.Combine(localStorageRootPath, jpgFile); // Copy the scene file to local storage sceneBlob.DownloadFile(sceneFilePath); // Run the ray tracer. string polyrayArguments = string.Format("\"{0}\" -o \"{1}\" -a 2", sceneFilePath, tgaFilePath); Process polyRayProcess = new Process(); polyRayProcess.StartInfo.FileName = Path.Combine(Environment.GetEnvironmentVariable("RoleRoot"), polyRayPath); polyRayProcess.StartInfo.Arguments = polyrayArguments; polyRayProcess.Start(); polyRayProcess.WaitForExit(); // Convert the image string dtaArguments = string.Format(" {0} /FJ /P{1}", tgaFilePath, Path.GetDirectoryName (jpgFilePath)); Process dtaProcess = new Process(); dtaProcess.StartInfo.FileName = Path.Combine(Environment.GetEnvironmentVariable("RoleRoot"), dtaPath); dtaProcess.StartInfo.Arguments = dtaArguments; dtaProcess.Start(); dtaProcess.WaitForExit(); // Upload the image to blob storage imageBlob.UploadFile(jpgFilePath); // Add a download job. downloadQueue.Add(jpgFile); // Delete the render job message jobQueue.Delete(jobMsg); Frames++; } else { Thread.Sleep(1000); } // Log the worker role activity. roleLifecycleDataSource.Alive ("CloudRayWorker", RoleLifecycleDataSource.RoleLifecycleId, Frames); } } Monitoring Worker Role Instance Lifecycle In order to get more accurate statistics about the lifecycle of the worker role instances used to render the animation data was tracked in an Azure storage table. The following class was used to track the worker role lifecycles in Azure storage. public class RoleLifecycle : TableServiceEntity { public string ServerName { get; set; } public string Status { get; set; } public DateTime StartTime { get; set; } public DateTime EndTime { get; set; } public long SecondsRunning { get; set; } public DateTime LastActiveTime { get; set; } public int Frames { get; set; } public string Comment { get; set; } public RoleLifecycle() { } public RoleLifecycle(string roleName) { PartitionKey = roleName; RowKey = Utils.GetAscendingRowKey(); Status = "Started"; StartTime = DateTime.UtcNow; LastActiveTime = StartTime; EndTime = StartTime; SecondsRunning = 0; Frames = 0; } } A new instance of this class is created and added to the storage table when the role starts. It is then updated each time the worker renders a frame to record the total number of frames rendered and the total processing time. These statistics are used be the monitoring application to determine the effectiveness of use of resources in the render farm. Rendering the Animation The Azure solution was deployed to Windows Azure with the service configuration set to 16 worker role instances. This allows for the application to be tested in the cloud environment, and the performance of the application determined. When I demo the application at conferences and user groups I often start with 16 instances, and then scale up the application to the full 256 instances. The configuration to run 16 instances is shown below. <?xml version="1.0" encoding="utf-8"?> <ServiceConfiguration serviceName="CloudRay" xmlns="http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceConfiguration" osFamily="1" osVersion="*"> <Role name="CloudRayWorkerRole"> <Instances count="16" /> <ConfigurationSettings> <Setting name="DataConnectionString" value="DefaultEndpointsProtocol=https;AccountName=cloudraydata;AccountKey=..." /> </ConfigurationSettings> </Role> </ServiceConfiguration> About six minutes after deploying the application the first worker roles become active and start to render the first frames of the animation. The CloudRay Monitor application displays an icon for each worker role instance, with a number indicating the number of frames that the worker role has rendered. The statistics on the left show the number of active worker roles and statistics about the render process. The render time is the time since the first worker role became active; the CPU time is the total amount of processing time used by all worker role instances to render the frames. Five minutes after the first worker role became active the last of the 16 worker roles activated. By this time the first seven worker roles had each rendered one frame of the animation. With 16 worker roles u and running it can be seen that one hour and 45 minutes CPU time has been used to render 32 frames with a render time of just under 10 minutes. At this rate it would take over 10 hours to render the 2,000 frames of the full animation. In order to complete the animation in under an hour more processing power will be required. Scaling the render farm from 16 instances to 256 instances is easy using the new management portal. The slider is set to 256 instances, and the configuration saved. We do not need to re-deploy the application, and the 16 instances that are up and running will not be affected. Alternatively, the configuration file for the Azure service could be modified to specify 256 instances. <?xml version="1.0" encoding="utf-8"?> <ServiceConfiguration serviceName="CloudRay" xmlns="http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceConfiguration" osFamily="1" osVersion="*"> <Role name="CloudRayWorkerRole"> <Instances count="256" /> <ConfigurationSettings> <Setting name="DataConnectionString" value="DefaultEndpointsProtocol=https;AccountName=cloudraydata;AccountKey=..." /> </ConfigurationSettings> </Role> </ServiceConfiguration> Six minutes after the new configuration has been applied 75 new worker roles have activated and are processing their first frames. Five minutes later the full configuration of 256 worker roles is up and running. We can see that the average rate of frame rendering has increased from 3 to 12 frames per minute, and that over 17 hours of CPU time has been utilized in 23 minutes. In this test the time to provision 140 worker roles was about 11 minutes, which works out at about one every five seconds. We are now half way through the rendering, with 1,000 frames complete. This has utilized just under three days of CPU time in a little over 35 minutes. The animation is now complete, with 2,000 frames rendered in a little over 52 minutes. The CPU time used by the 256 worker roles is 6 days, 7 hours and 22 minutes with an average frame rate of 38 frames per minute. The rendering of the last 1,000 frames took 16 minutes 27 seconds, which works out at a rendering rate of 60 frames per minute. The frame counts in the server instances indicate that the use of a queue to distribute the workload has been very effective in distributing the load across the 256 worker role instances. The first 16 instances that were deployed first have rendered between 11 and 13 frames each, whilst the 240 instances that were added when the application was scaled have rendered between 6 and 9 frames each. Completed Animation I’ve uploaded the completed animation to YouTube, a low resolution preview is shown below. Pin Board Animation Created using Windows Kinect and 256 Windows Azure Worker Roles The animation can be viewed in 1280x720 resolution at the following link: http://www.youtube.com/watch?v=n5jy6bvSxWc Effective Use of Resources According to the CloudRay monitor statistics the animation took 6 days, 7 hours and 22 minutes CPU to render, this works out at 152 hours of compute time, rounded up to the nearest hour. As the usage for the worker role instances are billed for the full hour, it may have been possible to render the animation using fewer than 256 worker roles. When deciding the optimal usage of resources, the time required to provision and start the worker roles must also be considered. In the demo I started with 16 worker roles, and then scaled the application to 256 worker roles. It would have been more optimal to start the application with maybe 200 worker roles, and utilized the full hour that I was being billed for. This would, however, have prevented showing the ease of scalability of the application. The new management portal displays the CPU usage across the worker roles in the deployment. The average CPU usage across all instances is 93.27%, with over 99% used when all the instances are up and running. This shows that the worker role resources are being used very effectively. Grid Computing Scenarios Although I am using this scenario for a hobby project, there are many scenarios where a large amount of compute power is required for a short period of time. Windows Azure provides a great platform for developing these types of grid computing applications, and can work out very cost effective. · Windows Azure can provide massive compute power, on demand, in a matter of minutes. · The use of queues to manage the load balancing of jobs between role instances is a simple and effective solution. · Using a cloud-computing platform like Windows Azure allows proof-of-concept scenarios to be tested and evaluated on a very low budget. · No charges for inbound data transfer makes the uploading of large data sets to Windows Azure Storage services cost effective. (Transaction charges still apply.) Tips for using Windows Azure for Grid Computing Scenarios I found the implementation of a render farm using Windows Azure a fairly simple scenario to implement. I was impressed by ease of scalability that Azure provides, and by the short time that the application took to scale from 16 to 256 worker role instances. In this case it was around 13 minutes, in other tests it took between 10 and 20 minutes. The following tips may be useful when implementing a grid computing project in Windows Azure. · Using an Azure Storage queue to load-balance the units of work across multiple worker roles is simple and very effective. The design I have used in this scenario could easily scale to many thousands of worker role instances. · Windows Azure accounts are typically limited to 20 cores. If you need to use more than this, a call to support and a credit card check will be required. · Be aware of how the billing model works. You will be charged for worker role instances for the full clock our in which the instance is deployed. Schedule the workload to start just after the clock hour has started. · Monitor the utilization of the resources you are provisioning, ensure that you are not paying for worker roles that are idle. · If you are deploying third party applications to worker roles, you may well run into licensing issues. Purchasing software licenses on a per-processor basis when using hundreds of processors for a short time period would not be cost effective. · Third party software may also require installation onto the worker roles, which can be accomplished using start-up tasks. Bear in mind that adding a startup task and possible re-boot will add to the time required for the worker role instance to start and activate. An alternative may be to use a prepared VM and use VM roles. · Consider using the Windows Azure Autoscaling Application Block (WASABi) to autoscale the worker roles in your application. When using a large number of worker roles, the utilization must be carefully monitored, if the scaling algorithms are not optimal it could get very expensive!

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iPhone SDK vs Windows Phone 7 Series SDK Challenge, Part 1: Hello World!

In this series, I will be taking sample applications from the iPhone SDK and implementing them on Windows Phone 7 Series. My goal is to do as much of an apples-to-apples comparison as I can. This series will be written to not only compare and contrast how easy or difficult it is to complete tasks on either platform, how many lines of code, etc., but Id also like it to be a way for iPhone developers to either get started on Windows Phone 7 Series development, or for developers in general to learn the platform. Heres my methodology: Run the iPhone SDK app in the iPhone Simulator to get a feel for what it does and how it works, without looking at the implementation Implement the equivalent functionality on Windows Phone 7 Series using Silverlight. Compare the two implementations based on complexity, functionality, lines of code, number of files, etc. Add some functionality to the Windows Phone 7 Series app that shows off a way to make the scenario more interesting or leverages an aspect of the platform, or uses a better design pattern to implement the functionality. You can download Microsoft Visual Studio 2010 Express for Windows Phone CTP here, and the Expression Blend 4 Beta here. Hello World! Of course no first post would be allowed if it didnt focus on the hello world scenario. The iPhone SDK follows that tradition with the Your First iPhone Application walkthrough. I will say that the developer documentation for iPhone is pretty good. There are plenty of walkthoughs and they break things down into nicely sized steps and do a good job of bringing the user along. As expected, this application is quite simple. It comprises of a text box, a label, and a button. When you push the button, the label changes to Hello plus the word you typed into the text box. Makes perfect sense for a starter application. Theres not much to this but it covers a few basic elements: Laying out basic UI Handling user input Hooking up events Formatting text So, lets get started building a similar app for Windows Phone 7 Series! Implementing the UI: UI in Silverlight (and therefore Windows Phone 7) is defined in XAML, which is a declarative XML language also used by WPF on the desktop. For anyone thats familiar with similar types of markup, its relatively straightforward to learn, but has a lot of power in it once you get it figured out. Well talk more about that. This UI is very simple. When I look at this, I note a couple of things: Elements are arranged vertically They are all centered So, lets create our Application and then start with the UI. Once you have the the VS 2010 Express for Windows Phone tool running, create a new Windows Phone Project, and call it Hello World: Once created, youll see the designer on one side and your XAML on the other: Now, we can create our UI in one of three ways: Use the designer in Visual Studio to drag and drop the components Use the designer in Expression Blend 4 to drag and drop the components Enter the XAML by hand in either of the above Well start with (1), then kind of move to (3) just for instructional value. To develop this UI in the designer: First, delete all of the markup between inside of the Grid element (LayoutRoot). You should be left with just this XAML for your MainPage.xaml (i shortened all the xmlns declarations below for brevity): 1: <phoneNavigation:PhoneApplicationPage 2: x:Class="HelloWorld.MainPage" 3: xmlns="...[snip]" 4: FontFamily="{StaticResource PhoneFontFamilyNormal}" 5: FontSize="{StaticResource PhoneFontSizeNormal}" 6: Foreground="{StaticResource PhoneForegroundBrush}"> 7: 8: <Grid x:Name="LayoutRoot" Background="{StaticResource PhoneBackgroundBrush}"> 9: 10: </Grid> 11: 12: </phoneNavigation:PhoneApplicationPage> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Well be adding XAML at line 9, so thats the important part. Now, Click on the center area of the phone surface Open the Toolbox and double click StackPanel Double click TextBox Double click TextBlock Double click Button That will create the necessary UI elements but they wont be arranged quite right. Well fix it in a second. Heres the XAML that we end up with: 1: <StackPanel Height="100" HorizontalAlignment="Left" Margin="10,10,0,0" Name="stackPanel1" VerticalAlignment="Top" Width="200"> 2: <TextBox Height="32" Name="textBox1" Text="TextBox" Width="100" /> 3: <TextBlock Height="23" Name="textBlock1" Text="TextBlock" /> 4: <Button Content="Button" Height="70" Name="button1" Width="160" /> 5: </StackPanel> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The designer does its best at guessing what we want, but in this case we want things to be a bit simpler. So well just clean it up a bit. We want the items to be centered and we want them to have a little bit of a margin on either side, so heres what we end up with. Ive also made it match the values and style from the iPhone app: 1: <StackPanel Margin="10"> 2: <TextBox Name="textBox1" HorizontalAlignment="Stretch" Text="You" TextAlignment="Center"/> 3: <TextBlock Name="textBlock1" HorizontalAlignment="Center" Margin="0,100,0,0" Text="Hello You!" /> 4: <Button Name="button1" HorizontalAlignment="Center" Margin="0,150,0,0" Content="Hello"/> 5: </StackPanel> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now lets take a look at what weve done there. Line 1: We removed all of the formatting from the StackPanel, except for Margin, as thats all we need. Since our parent element is a Grid, by default the StackPanel will be sized to fit in that space. The Margin says that we want to reserve 10 pixels on each side of the StackPanel. Line 2: Weve set the HorizontalAlignment of the TextBox to Stretch, which says that it should fill its parents size horizontally. We want to do this so the TextBox is always full-width. We also set TextAlignment to Center, to center the text. Line 3: In contrast to the TextBox above, we dont care how wide the TextBlock is, just so long as it is big enough for its text. Thatll happen automatically, so we just set its Horizontal alignment to Center. We also set a Margin above the TextBlock of 100 pixels to bump it down a bit, per the iPhone UI. Line 4: We do the same things here as in Line 3. Heres how the UI looks in the designer: Believe it or not, were almost done! Implementing the App Logic Now, we want the TextBlock to change its text when the Button is clicked. In the designer, double click the Button to be taken to the Event Handler for the Buttons Click event. In that event handler, we take the Text property from the TextBox, and format it into a string, then set it into the TextBlock. Thats it! 1: private void button1_Click(object sender, RoutedEventArgs e) 2: { 3: string name = textBox1.Text; 4: 5: // if there isn't a name set, just use "World" 6: if (String.IsNullOrEmpty(name)) 7: { 8: name = "World"; 9: } 10: 11: // set the value into the TextBlock 12: textBlock1.Text = String.Format("Hello {0}!", name); 13: 14: } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } We use the String.Format() method to handle the formatting for us. Now all thats left is to test the app in the Windows Phone Emulator and verify it does what we think it does! And it does! Comparing against the iPhone Looking at the iPhone example, there are basically three things that you have to touch as the developer: 1) The UI in the Nib file 2) The app delegate 3) The view controller Counting lines is a bit tricky here, but to try to keep this even, Im going to only count lines of code that I could not have (or would not have) generated with the tooling. Meaning, Im not counting XAML and Im not counting operations that happen in the Nib file with the XCode designer tool. So in the case of the above, even though I modified the XAML, I could have done all of those operations using the visual designer tool. And normally I would have, but the XAML is more instructive (and less steps!). Im interested in things that I, as the developer have to figure out in code. Im also not counting lines that just have a curly brace on them, or lines that are generated for me (e.g. method names that are generated for me when I make a connection, etc.) So, by that count, heres what I get from the code listing for the iPhone app found here: HelloWorldAppDelegate.h: 6 HelloWorldAppDelegate.m: 12 MyViewController.h: 8 MyViewController.m: 18 Which gives me a grand total of about 44 lines of code on iPhone. I really do recommend looking at the iPhone code for a comparison to the above. Now, for the Windows Phone 7 Series application, the only code I typed was in the event handler above Main.Xaml.cs: 4 So a total of 4 lines of code on Windows Phone 7. And more importantly, the process is just A LOT simpler. For example, I was surprised that the User Interface Designer in XCode doesnt automatically create instance variables for me and wire them up to the corresponding elements. I assumed I wouldnt have to write this code myself (and risk getting it wrong!). I dont need to worry about view controllers or anything. I just write my code. This blog post up to this point has covered almost every aspect of this apps development in a few pages. The iPhone tutorial has 5 top level steps with 2-3 sub sections of each. Now, its worth pointing out that the iPhone development model uses the Model View Controller (MVC) pattern, which is a very flexible and powerful pattern that enforces proper separation of concerns. But its fairly complex and difficult to understand when you first walk up to it. Here at Microsoft weve dabbled in MVC a bit, with frameworks like MFC on Visual C++ and with the ASP.NET MVC framework now. Both are very powerful frameworks. But one of the reasons weve stayed away from MVC with client UI frameworks is that its difficult to tool. We havent seen the type of value that beats double click, write code! for the broad set of scenarios. Another thing to think about is how many of those lines of code were focused on my apps functionality?. Or, the converse of How many lines of code were boilerplate plumbing? In both examples, the actual number of functional code lines is similar. I count most of them in MyViewController.m, in the changeGreeting method. Its about 7 lines of code that do the work of taking the value from the TextBox and putting it into the label. Versus 4 on the Windows Phone 7 side. But, unfortunately, on iPhone I still have to write that other 37 lines of code, just to get there. 10% of the code, 1 file instead of 4, its just much simpler. Making Some Tweaks It turns out, I can actually do this application with ZERO lines of code, if Im willing to change the spec a bit. The data binding functionality in Silverlight is incredibly powerful. And what I can do is databind the TextBoxs value directly to the TextBlock. Take some time looking at this XAML below. Youll see that I have added another nested StackPanel and two more TextBlocks. Why? Because thats how I build that string, and the nested StackPanel will lay things out Horizontally for me, as specified by the Orientation property. 1: <StackPanel Margin="10"> 2: <TextBox Name="textBox1" HorizontalAlignment="Stretch" Text="You" TextAlignment="Center"/> 3: <StackPanel Orientation="Horizontal" HorizontalAlignment="Center" Margin="0,100,0,0" > 4: <TextBlock Text="Hello " /> 5: <TextBlock Name="textBlock1" Text="{Binding ElementName=textBox1, Path=Text}" /> 6: <TextBlock Text="!" /> 7: </StackPanel> 8: <Button Name="button1" HorizontalAlignment="Center" Margin="0,150,0,0" Content="Hello" Click="button1_Click" /> 9: </StackPanel> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now, the real action is there in the bolded TextBlock.Text property: Text="{Binding ElementName=textBox1, Path=Text}" .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } That does all the heavy lifting. It sets up a databinding between the TextBox.Text property on textBox1 and the TextBlock.Text property on textBlock1. As I change the text of the TextBox, the label updates automatically. In fact, I dont even need the button any more, so I could get rid of that altogether. And no button means no event handler. No event handler means no C# code at all. Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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