Search Results

Search found 25005 results on 1001 pages for 'sequential number'.

Page 221/1001 | < Previous Page | 217 218 219 220 221 222 223 224 225 226 227 228  | Next Page >

• Confirm disk is broken when it passes all diagnostics

  - by Halfgaar

  I have a system with a potentially broken disk, but the disk passes all manner of diagnostics. I have been unable to confirm that the disk is broken. What are my options? I could just replace the disk, but because this situation is very similar to another more severe situation I have (long story), I'd like to actually make a proper diagnosis as opposed to randomly binning hardware. The issue and history is this: I had a Debian Linux PC (500 MHz P3) acting as router, nagios and munin. It crashed every couple of weeks. No logs or dmesg could be obtained (because it's an old Compaq that only boots when you configure it as keyboardless, making connecting a keyboard later, once it's booted, impossible). At the time, I just replaced the computer with another Compaq (P4 2.4 GHz) because I thought the hardware was faulty. However, it still crashed every couple of weeks. the difference is that on this computer, I can still SSH into it. It gives all kinds of errors on hda. I'd like to confirm that the disk is broken, but nothing I do confirms this: SMART error logs shows no errors. Normally when a disk starts acting up, SMART my pass, but it still records a read-error in the error log. SMART self-test (smartctl -t long /dev/sda) completes without errors. re-allocated sector count (a tell-tale parameter) has been 31 all its life, even when the disk was still in use in my desktop PC years ago, and it still is. The figure never changed. dd if=/dev/sda of=/dev/null bs=4096 passes with flying colors. What else can I do to assess the health of the drive? Again, this is not about making this router fully functional again, this is a disk forensic question, because it just so happens that I have another server that potentially has the same problem, and knowing the answer to this will possibly help me greatly. For the record, below are logs and such. This is the smartctl -a output: smartctl 5.40 2010-07-12 r3124 [i686-pc-linux-gnu] (local build) Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net === START OF INFORMATION SECTION === Model Family: Seagate Barracuda 7200.7 and 7200.7 Plus family Device Model: ST3120026A Serial Number: 5JT1CLQM Firmware Version: 3.06 User Capacity: 120,034,123,776 bytes Device is: In smartctl database [for details use: -P show] ATA Version is: 6 ATA Standard is: ATA/ATAPI-6 T13 1410D revision 2 Local Time is: Mon Jul 1 21:18:33 2013 CEST SMART support is: Available - device has SMART capability. SMART support is: Enabled === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: PASSED General SMART Values: Offline data collection status: (0x82) Offline data collection activity was completed without error. Auto Offline Data Collection: Enabled. Self-test execution status: ( 24) The self-test routine was aborted by the host. Total time to complete Offline data collection: ( 430) seconds. Offline data collection capabilities: (0x5b) SMART execute Offline immediate. Auto Offline data collection on/off support. Suspend Offline collection upon new command. Offline surface scan supported. Self-test supported. No Conveyance Self-test supported. Selective Self-test supported. SMART capabilities: (0x0003) Saves SMART data before entering power-saving mode. Supports SMART auto save timer. Error logging capability: (0x01) Error logging supported. No General Purpose Logging support. Short self-test routine recommended polling time: ( 1) minutes. Extended self-test routine recommended polling time: ( 85) minutes. SMART Attributes Data Structure revision number: 10 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x000f 050 046 006 Pre-fail Always - 47766662 3 Spin_Up_Time 0x0003 097 096 000 Pre-fail Always - 0 4 Start_Stop_Count 0x0032 100 100 020 Old_age Always - 10 5 Reallocated_Sector_Ct 0x0033 100 100 036 Pre-fail Always - 31 7 Seek_Error_Rate 0x000f 084 060 030 Pre-fail Always - 820305 9 Power_On_Hours 0x0032 048 048 000 Old_age Always - 46373 10 Spin_Retry_Count 0x0013 100 100 097 Pre-fail Always - 0 12 Power_Cycle_Count 0x0032 100 100 020 Old_age Always - 605 194 Temperature_Celsius 0x0022 036 065 000 Old_age Always - 36 195 Hardware_ECC_Recovered 0x001a 050 046 000 Old_age Always - 47766662 197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0010 100 100 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x003e 200 196 000 Old_age Always - 6 200 Multi_Zone_Error_Rate 0x0000 100 253 000 Old_age Offline - 0 202 Data_Address_Mark_Errs 0x0032 100 253 000 Old_age Always - 0 SMART Error Log Version: 1 No Errors Logged SMART Self-test log structure revision number 1 Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error # 1 Extended offline Aborted by host 80% 46361 - # 2 Extended offline Completed without error 00% 46358 - # 3 Short offline Completed without error 00% 12046 - # 4 Extended offline Completed without error 00% 10472 - # 5 Short offline Completed without error 00% 10471 - # 6 Short offline Completed without error 00% 10471 - # 7 Short offline Completed without error 00% 6770 - # 8 Extended offline Aborted by host 90% 5958 - # 9 Extended offline Aborted by host 90% 5951 - #10 Short offline Completed without error 00% 5024 - #11 Extended offline Aborted by host 80% 5024 - #12 Short offline Completed without error 00% 3697 - #13 Short offline Completed without error 00% 237 - #14 Short offline Completed without error 00% 145 - #15 Short offline Completed without error 00% 69 - #16 Extended offline Completed without error 00% 68 - #17 Short offline Completed without error 00% 66 - #18 Short offline Completed without error 00% 49 - #19 Short offline Completed without error 00% 29 - #20 Short offline Completed without error 00% 29 - SMART Selective self-test log data structure revision number 1 SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS 1 0 0 Not_testing 2 0 0 Not_testing 3 0 0 Not_testing 4 0 0 Not_testing 5 0 0 Not_testing Selective self-test flags (0x0): After scanning selected spans, do NOT read-scan remainder of disk. If Selective self-test is pending on power-up, resume after 0 minute delay. And this is the dmesg error when it has crashed (which repeats for a bunch of different sectors): [1755091.211136] sd 0:0:0:0: [sda] Unhandled error code [1755091.211144] sd 0:0:0:0: [sda] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK [1755091.211151] sd 0:0:0:0: [sda] CDB: Read(10): 28 00 08 fe ad 38 00 00 08 00 [1755091.211166] end_request: I/O error, dev sda, sector 150908216

  Read the article

• RAID Array performance on an HP Proliant ML350 G5 Smart Array E200i

  - by Nate Pinchot

  We have a client who is complaining about performance of an application which utilizes an MS SQL database. They do not believe the performance issues are the fault of the application itself. The Smart Array E200i RAID controller has 128MB cache and we have the cache set to 75% read/25% write. The disk array set to enable write caching. Recently we ran a disk performance test using SQLIO based on this guide. We used a 10 GB file for the test found that the average sequential read rate was ~60 MB/sec (megabytes/sec) and the average random read rate was ~30 MB/sec. Are these numbers on par for what the server should be performing? Better than on par? Horrible? Amazing?

  Read the article

• Making a tab key on the right side of a full sized mac keyboard

  - by StoneBreaker

  I use mac OSX with a full sized keyboard (F1-F19, number pad arrow keys and FN, Home, End, Page UP/Down delete mini pad above the arrow keys). My mouse is on the left side of the keyboard. This allows use of the return key, the arrow keys and the number pad etc. with my right hand. I would like to assign a key or key combination on the right side of the keyboard to operate the same as the tab key. I am thinking a Function key or the Home key, or FN+?? I have QuickKeys and could use that if someone knows how. If there is no way to make a key the equivalent of the tab key, then at the least I would like to make some equivalent to Cmd+Tab that I can use with my right hand. Thanks for any help and ideas.

  Read the article

• Can I completely remove the Windows DNS in favour of BIND9 in an AD network?

  - by Vinícius Ferrão

  I would like to remove the DNS feature of Windows Domain Controllers and point the DNS servers to our BIND9 servers. I know it's possible to setup coexistence but this requires a number of extra Windows DNS Servers equals to the number of Domain Controllers in the network. Active Directory expects the _msdcs zone and other things like _tcp, _udp; etc. The main question is: how to make BIND9 takes care of all this AD specific data? And with dynamic updating to make AD even more happier. Thanks, PS: Making BIND9 points to the Windows DNS Servers to resolve the Active Directory specific zones isn't an option. We already do this... EDIT: As today, I'm running without Windows DNS. I'm writing up a guide on how to do this, and I'll update this topic.

  Read the article

• Why would you ever set MaxKeepAliveRequests to anything but unlimited?

  - by Jonathon Reinhart

  Apache's KeepAliveTimeout exists to close a keep-alive connection if a new request is not issued within a given period of time. Provided the user does not close his browser/tab, this timeout (usually 5-15 seconds) is what eventually closes most keep-alive connections, and prevents server resources from being wasted by holding on to connections indefinitely. Now the MaxKeepAliveRequests directive puts a limit on the number of HTTP requests that a single TCP connection (left open due to KeepAlive) will serve. Setting this to 0 means an unlimited number of requests are allowed. Why would you ever set this to anything but "unlimited"? Provided a client is still actively making requests, what harm is there in letting them happen on the same keep-alive connection? Once the limit is reached, the requests still come in, just on a new connection. The way I see it, there is no point in ever limiting this. What am I missing?

  Read the article

• How to use multiple SkyDrive accounts on one computer?

  - by user1563721

  Is there any way how to use multiple SkyDrive accounts on one computer running MAC OS X or Windows 8? I would like to sync data from different accounts to different folder and not to merge these accounts to one. The reason is that every SkyDrive has it's storage limits and I'm using every account for different work data. The result should be the following: I have a number of SkyDrive accounts every for different work, let's say: S1 S2 S3 I would like to sync exactly the same number of folders on computer using different accounts to sync them: SkyDriveS1Folder - (folder on computer which syncing the content of S1 SkyDrive) SkyDriveS2Folder - (folder on computer which syncing the content of S2 SkyDrive) SkyDriveS3Folder - (folder on computer which syncing the content of S3 SkyDrive) Is it possible somehow? I found a workaround for Windows machines (http://superuser.com/questions/525932/running-multiple-instances-of-microsoft-skydrive) but is there anything for MAC OS X machines? Or is it possible through any third party application?

  Read the article

• Enjoy Seamless Reading at Twitter in Chrome

  - by Asian Angel

  Twitter can be a lot of fun but having to constantly use the More Button to view a large number of tweets is frustrating. All that you need to be rid of that frustration is the More Tweets! extension for Google Chrome. Before Here it is…the classic “More Button”. If you are only interested in viewing a few tweets on occasion then it is not a problem. But if you are looking at a large number of tweets on a daily basis then it can be very frustrating. Notice the last tweet from TinyHacker shown here… After After installing the extension the only thing that you will need to do is refresh your Twitter page if you had it open before-hand. Now there will be a seamless connection from page to page when you are reading through tweets. You can see the TinyHacker tweet from above followed oh so nicely by tweets from the second page…this is definitely an improvement. For those who may be curious if you are quick enough with your mouse you can see what the “automated connection process” looks like. Conclusion If you are tired of constantly clicking the “More Button” and just want to read tweets without interruption then you will be very satisfied after adding this extension to your browser. Links Download the More Tweets! extension (Google Chrome Extensions) Similar Articles Productive Geek Tips Integrate Twitter With Microsoft OutlookMake Mail.app’s Reading Pane More Like OutlookBlip.fm is a Fun Social Way to Share MusicDisable YouTube Comments while using ChromeAdd Shareaholic Goodness to Google Chrome TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Classic Cinema Online offers 100’s of OnDemand Movies OutSync will Sync Photos of your Friends on Facebook and Outlook Windows 7 Easter Theme YoWindoW, a real time weather screensaver Optimize your computer the Microsoft way Stormpulse provides slick, real time weather data

  Read the article

• dependency problems at installation from mysql-server-5.5

  - by Furtano

  qcons@014-QCONS:/var/lib$ sudo apt-get install -f mysql-server Paketlisten werden gelesen... Fertig Abhängigkeitsbaum wird aufgebaut Statusinformationen werden eingelesen... Fertig mysql-server ist schon die neueste Version. 0 aktualisiert, 0 neu installiert, 0 zu entfernen und 0 nicht aktualisiert. 2 nicht vollständig installiert oder entfernt. Nach dieser Operation werden 0 B Plattenplatz zusätzlich benutzt. Möchten Sie fortfahren [J/n]? j mysql-server-5.5 (5.5.28-0ubuntu0.12.04.2) wird eingerichtet ... 121112 11:16:52 [Note] Plugin 'FEDERATED' is disabled. 121112 11:16:52 InnoDB: The InnoDB memory heap is disabled 121112 11:16:52 InnoDB: Mutexes and rw_locks use GCC atomic builtins 121112 11:16:52 InnoDB: Compressed tables use zlib 1.2.3.4 121112 11:16:52 InnoDB: Initializing buffer pool, size = 128.0M 121112 11:16:52 InnoDB: Completed initialization of buffer pool 121112 11:16:52 InnoDB: highest supported file format is Barracuda. 121112 11:16:53 InnoDB: Waiting for the background threads to start 121112 11:16:54 InnoDB: 1.1.8 started; log sequence number 1595675 121112 11:16:54 InnoDB: Starting shutdown... 121112 11:16:54 InnoDB: Shutdown completed; log sequence number 1595675 start: Job failed to start invoke-rc.d: initscript mysql, action "start" failed. dpkg: Fehler beim Bearbeiten von mysql-server-5.5 (--configure): Unterprozess installiertes post-installation-Skript gab den Fehlerwert 1 zurück dpkg: Abhängigkeitsprobleme verhindern Konfiguration von mysql-server: mysql-server hängt ab von mysql-server-5.5; aber: Paket mysql-server-5.5 ist noch nicht konfiguriert. dpkg: Fehler beim Bearbeiten von mysql-server (--configure): Abhängigkeitsprobleme - verbleibt unkonfiguriert Es wurde kein Apport-Bericht verfasst, da die Fehlermeldung darauf hindeutet, dass dies lediglich ein Folgefehler eines vorherigen Problems ist. Fehler traten auf beim Bearbeiten von: mysql-server-5.5 mysql-server E: Sub-process /usr/bin/dpkg returned an error code (1)

  Read the article

• Raid0 performance degradation?

  - by davy8

  Not sure if this belongs here or on SuperUser, feel free to move as appropriate. I've noticed the performance on my RAID0 setup seems to have degraded over the past months. The throughput is fine, but I think the random access time has increased or something. In use I generally see about 1-5mb/sec when loading stuff in Visual Studio and other apps and it doesn't seem like the CPU is bottlenecking as the CPU utilization is pretty low. I don't recall what Access Time used to be, but HD Tune is reporting 12.6ms Read throughput is showing as averaging about 125MB/sec so it should be great for sequential reads. Defrag daily and it shows fragmentation levels low, so that shouldn't be an issue. Additional info, Windows 7 x64, Intel raid controller on mobo, WD Black 500GB (I think 32mb cache) x2.

  Read the article

• Raid0 performance degradation?

  - by davy8

  Not sure if this belongs here or on SuperUser, feel free to move as appropriate. I've noticed the performance on my RAID0 setup seems to have degraded over the past months. The throughput is fine, but I think the random access time has increased or something. In use I generally see about 1-5mb/sec when loading stuff in Visual Studio and other apps and it doesn't seem like the CPU is bottlenecking as the CPU utilization is pretty low. I don't recall what Access Time used to be, but HD Tune is reporting 12.6ms Read throughput is showing as averaging about 125MB/sec so it should be great for sequential reads. Defrag daily and it shows fragmentation levels low, so that shouldn't be an issue. Additional info, Windows 7 x64, Intel raid controller on mobo, WD Black 500GB (I think 32mb cache) x2.

  Read the article

• Debuild fails to make package for bluelog-1.04

  - by Dean Howell

  When trying to build a package for bluelog, Debuild give several errors. In the past, I've used checkinstall to quickly build crude packages. I am now trying to do it the right way and upload to a PPA. Bluelog can be found here: http://www.digifail.com/software/bluelog.shtml Here is the output from debuild; dpkg-buildpackage -rfakeroot -D -us -uc dpkg-buildpackage: export CFLAGS from dpkg-buildflags (origin: vendor): -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Wformat-security dpkg-buildpackage: export CPPFLAGS from dpkg-buildflags (origin: vendor): -D_FORTIFY_SOURCE=2 dpkg-buildpackage: export CXXFLAGS from dpkg-buildflags (origin: vendor): -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Wformat-security dpkg-buildpackage: export FFLAGS from dpkg-buildflags (origin: vendor): -g -O2 dpkg-buildpackage: export LDFLAGS from dpkg-buildflags (origin: vendor): -Wl,-Bsymbolic-functions -Wl,-z,relro dpkg-buildpackage: source package bluelog dpkg-buildpackage: source version 1.0.4-0ubuntu1 dpkg-buildpackage: source changed by Dean Howell <dean@unknown> dpkg-source --before-build bluelog dpkg-buildpackage: host architecture amd64 fakeroot debian/rules clean dh clean dh_testdir dh_auto_clean make[1]: Entering directory `/home/dean/Launchpad Builds/bluelog/bluelog' rm -rf bluelog www/cgi-bin/* *.o *.txt *.log *.gz *.cgi make[1]: Leaving directory `/home/dean/Launchpad Builds/bluelog/bluelog' dh_clean dpkg-source -b bluelog dpkg-source: warning: Version number suggests Ubuntu changes, but Maintainer: does not have Ubuntu address dpkg-source: warning: Version number suggests Ubuntu changes, but there is no XSBC-Original-Maintainer field dpkg-source: info: using source format `3.0 (quilt)' dpkg-source: info: building bluelog using existing ./bluelog_1.0.4.orig.tar.gz dpkg-source: error: cannot represent change to bluelog/Builds/bluelog/bluelog/debian/bluelog/usr/bin/bluelog: binary file contents changed dpkg-source: error: add Builds/bluelog/bluelog/debian/bluelog/usr/bin/bluelog in debian/source/include-binaries if you want to store the modified binary in the debian tarball dpkg-source: error: unrepresentable changes to source dpkg-buildpackage: error: dpkg-source -b bluelog gave error exit status 2

  Read the article

• apache2 and php slow first load on Ubuntu VPS - something like mysqltuner but for apache?

  - by talkingnews

  Ubuntu 10.10 64 bit VPS, 512Mb dedicated RAM. Mysql tuned so that sqltuner is completely happy. Used RAM never above 350Mb out of the 493 available. Load never exceeds 1.04 or so. httpd.conf tuned as per all the guides for vps of that memory - amount of preforks, spares etc. But for the FIRST load a site after having not visited for a while, it's taking ages. First load: Parse Time: 3.576 - Number of Queries: 50 - Query Time: 0.019723195953369 Reload Parse Time: 0.096 - Number of Queries: 39 - Query Time: 0.0066126374511719 Subsequent reloads will be at this speed. htop shows two items as soon as I load that page for the first time: php-cgi /usr/sbin/apache2 -k start I'm using suPHP but I've tried fast-cgi and cgi. Stuck now, a weekend of tweaking has brought me nothing. Advice appreciated.

  Read the article

• Monitoring HP and Dell hardware in Gentoo.

  - by ewwhite

  I'm working in an environment that features a large number of Gentoo servers running on HP ProLiant and Dell PowerEdge equipment. While I've moved some of these systems to RedHat or CentOS for consistency, I'm still left with a good number of systems that will remain Gentoo. One of the issues I see with the Gentoo arrangement is lack of vendor-supported hardware monitoring. There doesn't seem to be an equivalent to the HP ProLiant Support Pack or Dell's agents for Gentoo. Is this simply something that you give up when using this distribution? How do you monitor hardware health and the like with Gentoo systems?

  Read the article

• Ubuntu 12.04, xbmc, opengl, intel motherboard

  - by Sean Hagen

  I've got an HTPC that I built myself, with a Asus P5G41T-M Motherboard. It's got an on-board HDMI port, and I've been using that with no problems. I started out with Mythbuntu ( an older version ), and recently updated to 12.04.1 LTS without any issues. I've been thinking about trying out XBMC for a while, and I decided to give it a go. Unfortunately, I seem to be running into quite a few issues. I got XBMC installed from the repos without any issues, but when I try to run it from a console, a box pops up with the following: XBMC needs hardware accelerated OpenGL rendering. Install an appropriate graphics driver. Please consule XBMC Wiki for supported hardware http://wiki.xbmc.org/?title=Supported_hardware In the console, it prints out the following: X Error of failed request: BadRequest (invalid request code or no such operation) Major opcode of failed request: 136 (GLX) Minor opcode of failed request: 19 (X_GLXQueryServerString) Serial number of failed request: 12 Current serial number in output stream: 12 When I run vainfo, I get this: libva: VA-API version 0.32.0 libva: va_getDriverName() returns 0 libva: Trying to open /usr/lib/x86_64-linux-gnu/dri/i965_drv_video.so libva: va_openDriver() returns 0 vainfo: VA-API version: 0.32 (libva 1.0.15) vainfo: Driver version: Intel i965 driver - 1.0.15 vainfo: Supported profile and entrypoints VAProfileMPEG2Simple : VAEntrypointVLD VAProfileMPEG2Main : VAEntrypointVLD The file /usr/lib/x86_64-linux-gnu/dri/i964_drv_video.so exists: # ls -l /usr/lib/x86_64-linux-gnu/dri/i965_drv_video.so -rw-r--r-- 1 root root 628728 Mar 29 2012 /usr/lib/x86_64-linux-gnu/dri/i965_drv_video.so And in /var/log/Xorg.0.log the following error pops up: GLX error: Can not get required symbols. I'm not really sure where to go from here. I've tried searching all over for how to fix this problem. I've done "apt-get --reinstall xserver-xorg" ( as well as a few other video driver packages ) a few times, and no change. Any help in getting this issue sorted out would be awesome.

  Read the article

• Server Fault Wiki: How does Subnetting Work?

  - by Kyle Brandt

  How does Subnetting Work, and How do you do it by hand or in your head? Can someone explain both conceptually and with several examples? Server Fault gets lots of subnetting homework questions, so we could use an answer to point them to on Server Fault itself. If I have a network, how do I figure out how to split it up? If I am given a netmask, how do I know what the network Range is for it? Sometimes there is a slash followed by a number, what is that number? Sometimes there is a subnet mask, but also a wildcard mask, they seem like the same thing but they are different? Someone mentioned something about knowing binary for this? Not looking for links to other sites (unless maybe you have one post with a bunch of good ones). I already know how to subnet, I just thought it would be nice if Server Fault had a generic subnetting answer.

  Read the article

• How to keep Flash secured with EMET?

  - by Indrek

  I use EMET to secure a number of applications on my computer - web browsers, Office suite applications, PDF readers, as well as Adobe Flash. Overall it's working great, except that the Flash executables contain the version number in the file name, so every time there's an update, the file names change and I have to remember to re-add them manually to EMET. Is there a way to streamline this process? EMET does support wildcards, but only in the path itself, not the file name, so something like %windir%\system32\Macromed\Flash\*.exe wouldn't work. Is there any other way to add a whole folder to EMET so that any new executables in that folder are automatically secured?

  Read the article

• Should I swap from WCF to NserviceBus

  - by Matt Roberts

  We have a central server that sends and recieves messages from a number of PCs that are located on client networks in various locations. To facilitate this, currently I'm using WCF with TCPNetBindings, using duplex communication secured with certificates. Now, we have a number of issues with this - mainly that we are being asked to support "disconnected mode" (we need to be fault tolerant). From what I know, there is no simple way to do this using the WCF stack - we'd need to implement something and perhaps use msmq. I've been looking at NServiceBus lately, and from I can see it seems to fit the bill well - fault tolerance, messages can be sent over the internet via a simple http gateway, etc. I know it's well respected in the community, and I can see why from looking into it. So, my question is...Does employing NServiceBus sound like a sensible idea, or does anyone have any other suggestions / real world experience that relate to this? I guess I'm worried of introducing a new tech that I know relatively little about, and facing problems with things like securing it, setting everything up in a reliable way, gotchas along the way.. I'm also wary of "gold-plating" the architecture, and choosing something shiny that will end up bogging me down in implementation versus sticking with WCF and just making it work for me.. Thanks!

  Read the article

• Skipping scheduled self-tests and predicting drive EOL

  - by Steve Madsen

  For a few weeks now, smartd has been reporting that it is skipping some of its scheduled self-tests on the weekends: Apr 24 18:29:32 calvin smartd[4758]: Device: /dev/sda, skip scheduled Offline Immediate Test; 40% remaining of current Self-Test. Apr 24 18:29:33 calvin smartd[4758]: Device: /dev/sdb, skip scheduled Offline Immediate Test; 50% remaining of current Self-Test. The drives in this RAID-1 array are set to run an offline test four times a day, a short self-test at 2am every day, and a long self-test on Saturdays at 2am. For some reason, it looks like the long self-test is taking longer, causing the other scheduled tests to be skipped. First question: is this a sign of likely drive failure? Then today, smartd reported that a self-test failed. Here is the output of smartctl -a /dev/sdb: smartctl version 5.38 [i686-pc-linux-gnu] Copyright (C) 2002-8 Bruce Allen Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Model Family: Seagate Barracuda 7200.8 family Device Model: ST3250823AS Serial Number: 3ND1GNBC Firmware Version: 3.03 User Capacity: 250,059,350,016 bytes Device is: In smartctl database [for details use: -P show] ATA Version is: 7 ATA Standard is: Exact ATA specification draft version not indicated Local Time is: Sun Apr 25 13:15:34 2010 EDT SMART support is: Available - device has SMART capability. SMART support is: Enabled === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: PASSED General SMART Values: Offline data collection status: (0x82) Offline data collection activity was completed without error. Auto Offline Data Collection: Enabled. Self-test execution status: ( 0) The previous self-test routine completed without error or no self-test has ever been run. Total time to complete Offline data collection: ( 430) seconds. Offline data collection capabilities: (0x5b) SMART execute Offline immediate. Auto Offline data collection on/off support. Suspend Offline collection upon new command. Offline surface scan supported. Self-test supported. No Conveyance Self-test supported. Selective Self-test supported. SMART capabilities: (0x0003) Saves SMART data before entering power-saving mode. Supports SMART auto save timer. Error logging capability: (0x01) Error logging supported. General Purpose Logging supported. Short self-test routine recommended polling time: ( 1) minutes. Extended self-test routine recommended polling time: ( 84) minutes. SMART Attributes Data Structure revision number: 10 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x000f 047 039 006 Pre-fail Always - 168450357 3 Spin_Up_Time 0x0003 098 098 000 Pre-fail Always - 0 4 Start_Stop_Count 0x0032 100 100 020 Old_age Always - 33 5 Reallocated_Sector_Ct 0x0033 100 100 036 Pre-fail Always - 9 7 Seek_Error_Rate 0x000f 087 060 030 Pre-fail Always - 654745480 9 Power_On_Hours 0x0032 055 055 000 Old_age Always - 40141 10 Spin_Retry_Count 0x0013 100 100 097 Pre-fail Always - 0 12 Power_Cycle_Count 0x0032 100 100 020 Old_age Always - 51 194 Temperature_Celsius 0x0022 037 062 000 Old_age Always - 37 (0 17 0 0) 195 Hardware_ECC_Recovered 0x001a 047 039 000 Old_age Always - 168450357 197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0010 100 100 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x003e 200 200 000 Old_age Always - 0 200 Multi_Zone_Error_Rate 0x0000 100 253 000 Old_age Offline - 0 202 TA_Increase_Count 0x0032 100 253 000 Old_age Always - 0 SMART Error Log Version: 1 No Errors Logged SMART Self-test log structure revision number 1 Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error # 1 Short offline Completed without error 00% 40131 - # 2 Extended offline Completed: read failure 30% 40129 379795511 # 3 Short offline Completed without error 00% 40084 - # 4 Short offline Completed without error 00% 40060 - # 5 Short offline Completed without error 00% 40036 - # 6 Short offline Completed without error 00% 40013 - # 7 Short offline Completed without error 00% 39990 - # 8 Extended offline Completed without error 00% 39977 - # 9 Short offline Completed without error 00% 39919 - #10 Short offline Completed without error 00% 39895 - #11 Short offline Completed without error 00% 39872 - #12 Short offline Completed without error 00% 39848 - #13 Short offline Completed without error 00% 39824 - #14 Short offline Completed without error 00% 39801 - #15 Extended offline Completed without error 00% 39789 - #16 Short offline Completed without error 00% 39754 - #17 Short offline Completed without error 00% 39732 - #18 Short offline Completed without error 00% 39707 - #19 Short offline Completed without error 00% 39683 - #20 Short offline Completed without error 00% 39660 - #21 Short offline Completed without error 00% 39636 - SMART Selective self-test log data structure revision number 1 SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS 1 0 0 Not_testing 2 0 0 Not_testing 3 0 0 Not_testing 4 0 0 Not_testing 5 0 0 Not_testing Selective self-test flags (0x0): After scanning selected spans, do NOT read-scan remainder of disk. If Selective self-test is pending on power-up, resume after 0 minute delay. Given that this drive is about 4.5 years old, I am probably tempting fate by keeping it in service. SMART doesn't seem to get much respect as a reliable way to predict drive failure. What else can I use to get an early indication of drive failure?

  Read the article

• Announcing: Great Improvements to Windows Azure Web Sites

  - by ScottGu

  I’m excited to announce some great improvements to the Windows Azure Web Sites capability we first introduced earlier this summer.  Today’s improvements include: a new low-cost shared mode scaling option, support for custom domains with shared and reserved mode web-sites using both CNAME and A-Records (the later enabling naked domains), continuous deployment support using both CodePlex and GitHub, and FastCGI extensibility.  All of these improvements are now live in production and available to start using immediately. New “Shared” Scaling Tier Windows Azure allows you to deploy and host up to 10 web-sites in a free, shared/multi-tenant hosting environment. You can start out developing and testing web sites at no cost using this free shared mode, and it supports the ability to run web sites that serve up to 165MB/day of content (5GB/month).  All of the capabilities we introduced in June with this free tier remain the same with today’s update. Starting with today’s release, you can now elastically scale up your web-site beyond this capability using a new low-cost “shared” option (which we are introducing today) as well as using a “reserved instance” option (which we’ve supported since June).  Scaling to either of these modes is easy.  Simply click on the “scale” tab of your web-site within the Windows Azure Portal, choose the scaling option you want to use with it, and then click the “save” button.  Changes take only seconds to apply and do not require any code to be changed, nor the app to be redeployed: Below are some more details on the new “shared” option, as well as the existing “reserved” option: Shared Mode With today’s release we are introducing a new low-cost “shared” scaling mode for Windows Azure Web Sites.  A web-site running in shared mode is deployed in a shared/multi-tenant hosting environment.  Unlike the free tier, though, a web-site in shared mode has no quotas/upper-limit around the amount of bandwidth it can serve.  The first 5 GB/month of bandwidth you serve with a shared web-site is free, and then you pay the standard “pay as you go” Windows Azure outbound bandwidth rate for outbound bandwidth above 5 GB. A web-site running in shared mode also now supports the ability to map multiple custom DNS domain names, using both CNAMEs and A-records, to it.  The new A-record support we are introducing with today’s release provides the ability for you to support “naked domains” with your web-sites (e.g. http://microsoft.com in addition to http://www.microsoft.com).  We will also in the future enable SNI based SSL as a built-in feature with shared mode web-sites (this functionality isn’t supported with today’s release – but will be coming later this year to both the shared and reserved tiers). You pay for a shared mode web-site using the standard “pay as you go” model that we support with other features of Windows Azure (meaning no up-front costs, and you pay only for the hours that the feature is enabled).  A web-site running in shared mode costs only 1.3 cents/hr during the preview (so on average $9.36/month). Reserved Instance Mode In addition to running sites in shared mode, we also support scaling them to run within a reserved instance mode.  When running in reserved instance mode your sites are guaranteed to run isolated within your own Small, Medium or Large VM (meaning no other customers run within it).  You can run any number of web-sites within a VM, and there are no quotas on CPU or memory limits. You can run your sites using either a single reserved instance VM, or scale up to have multiple instances of them (e.g. 2 medium sized VMs, etc).  Scaling up or down is easy – just select the “reserved” instance VM within the “scale” tab of the Windows Azure Portal, choose the VM size you want, the number of instances of it you want to run, and then click save.  Changes take effect in seconds: Unlike shared mode, there is no per-site cost when running in reserved mode.  Instead you pay only for the reserved instance VMs you use – and you can run any number of web-sites you want within them at no extra cost (e.g. you could run a single site within a reserved instance VM or 100 web-sites within it for the same cost).  Reserved instance VMs start at 8 cents/hr for a small reserved VM.  Elastic Scale-up/down Windows Azure Web Sites allows you to scale-up or down your capacity within seconds.  This allows you to deploy a site using the shared mode option to begin with, and then dynamically scale up to the reserved mode option only when you need to – without you having to change any code or redeploy your application. If your site traffic starts to drop off, you can scale back down the number of reserved instances you are using, or scale down to the shared mode tier – all within seconds and without having to change code, redeploy, or adjust DNS mappings.  You can also use the “Dashboard” view within the Windows Azure Portal to easily monitor your site’s load in real-time (it shows not only requests/sec and bandwidth but also stats like CPU and memory usage). Because of Windows Azure’s “pay as you go” pricing model, you only pay for the compute capacity you use in a given hour.  So if your site is running most of the month in shared mode (at 1.3 cents/hr), but there is a weekend when it gets really popular and you decide to scale it up into reserved mode to have it run in your own dedicated VM (at 8 cents/hr), you only have to pay the additional pennies/hr for the hours it is running in the reserved mode.  There is no upfront cost you need to pay to enable this, and once you scale back down to shared mode you return to the 1.3 cents/hr rate.  This makes it super flexible and cost effective. Improved Custom Domain Support Web sites running in either “shared” or “reserved” mode support the ability to associate custom host names to them (e.g. www.mysitename.com).  You can associate multiple custom domains to each Windows Azure Web Site.  With today’s release we are introducing support for A-Records (a big ask by many users). With the A-Record support, you can now associate ‘naked’ domains to your Windows Azure Web Sites – meaning instead of having to use www.mysitename.com you can instead just have mysitename.com (with no sub-name prefix).  Because you can map multiple domains to a single site, you can optionally enable both a www and naked domain for a site (and then use a URL rewrite rule/redirect to avoid SEO problems). We’ve also enhanced the UI for managing custom domains within the Windows Azure Portal as part of today’s release.  Clicking the “Manage Domains” button in the tray at the bottom of the portal now brings up custom UI that makes it easy to manage/configure them: As part of this update we’ve also made it significantly smoother/easier to validate ownership of custom domains, and made it easier to switch existing sites/domains to Windows Azure Web Sites with no downtime. Continuous Deployment Support with Git and CodePlex or GitHub One of the more popular features we released earlier this summer was support for publishing web sites directly to Windows Azure using source control systems like TFS and Git.  This provides a really powerful way to manage your application deployments using source control.  It is really easy to enable this from a website’s dashboard page: The TFS option we shipped earlier this summer provides a very rich continuous deployment solution that enables you to automate builds and run unit tests every time you check in your web-site, and then if they are successful automatically publish to Azure. With today’s release we are expanding our Git support to also enable continuous deployment scenarios and integrate with projects hosted on CodePlex and GitHub.  This support is enabled with all web-sites (including those using the “free” scaling mode). Starting today, when you choose the “Set up Git publishing” link on a website’s “Dashboard” page you’ll see two additional options show up when Git based publishing is enabled for the web-site: You can click on either the “Deploy from my CodePlex project” link or “Deploy from my GitHub project” link to walkthrough a simple workflow to configure a connection between your website and a source repository you host on CodePlex or GitHub.  Once this connection is established, CodePlex or GitHub will automatically notify Windows Azure every time a checkin occurs.  This will then cause Windows Azure to pull the source and compile/deploy the new version of your app automatically.  The below two videos walkthrough how easy this is to enable this workflow and deploy both an initial app and then make a change to it: Enabling Continuous Deployment with Windows Azure Websites and CodePlex (2 minutes) Enabling Continuous Deployment with Windows Azure Websites and GitHub (2 minutes) This approach enables a really clean continuous deployment workflow, and makes it much easier to support a team development environment using Git: Note: today’s release supports establishing connections with public GitHub/CodePlex repositories.  Support for private repositories will be enabled in a few weeks. Support for multiple branches Previously, we only supported deploying from the git ‘master’ branch.  Often, though, developers want to deploy from alternate branches (e.g. a staging or future branch). This is now a supported scenario – both with standalone git based projects, as well as ones linked to CodePlex or GitHub.  This enables a variety of useful scenarios.  For example, you can now have two web-sites - a “live” and “staging” version – both linked to the same repository on CodePlex or GitHub.  You can configure one of the web-sites to always pull whatever is in the master branch, and the other to pull what is in the staging branch.  This enables a really clean way to enable final testing of your site before it goes live. This 1 minute video demonstrates how to configure which branch to use with a web-site. Summary The above features are all now live in production and available to use immediately.  If you don’t already have a Windows Azure account, you can sign-up for a free trial and start using them today.  Visit the Windows Azure Developer Center to learn more about how to build apps with it. We’ll have even more new features and enhancements coming in the weeks ahead – including support for the recent Windows Server 2012 and .NET 4.5 releases (we will enable new web and worker role images with Windows Server 2012 and .NET 4.5 next month).  Keep an eye out on my blog for details as these new features become available. Hope this helps, 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

  Read the article

• Slow speeds on Samsung SSD PM800 256gb on a Lenovo W500

  - by cc0

  I recently bought a W500 with a 256gb samsung ssd drive. Now it seems ridiculously slow at writing. I am copying files at about 30mb/s, but I can read them at about 200mb/s. I tested it with the AS SSD Benchmark v1.4, and got a sequential writing speed of 34.64mb/s and reading speed of 196.95mb/s When I bought it the drive had only been in use for about 240 hours, and according to the CrystalDiskInfo app it had 98% health. Is there a bottleneck here somewhere? Or is the drive just plain bad. I'd really love it if someone could help me find some answers. The main relevant (I hope) w500 specs for this machine are; T9600 @ 2.8ghz 4gb ddr3

  Read the article

• Help make sense of a KillDisk error/log

  - by user284194

  I have a hard drive that I've been trying to reformat. I tried reformatting it in the windows XP and 7 installers, and in an Ubuntu live cd with gparted. I tried using dd to 'zero' the drive as well with no success. Finally I ran across KillDisk after a search. I tried to zero the disk again with KillDisk and after 8 hours of zeroing I get the following errors in the log: ----------------------------------------Erase Session Begin--------------------------------------- 2010-03-23 19:35:54 Active@ KILLDISK for Windows Build 5.1.39 started Target: WDC WD2500KS-00MJB0 232.9 GB Located on: WDC WD2500KS-00MJB0 (Serial number: WD-WCANK9604799) Erase method: One Pass Zeros (1 pass) Passes: 1 Bad (unwritable) sectors detected from 1701 to 488397167 on Hard Disk 1. Error (the handle is invalid) refreshing device Hard Disk 1. Error (the handle is invalid) reading sector 0 on 81h. 2010-03-24 02:28:25 Total number of erased device(s): 0, partition(s): 0 -----------------------------------------Erase Session End---------------------------------------- Is the drive dead?

  Read the article

• quick look at: dm_db_index_physical_stats

  - by fatherjack

  A quick look at the key data from this dmv that can help a DBA keep databases performing well and systems online as the users need them. When the dynamic management views relating to index statistics became available in SQL Server 2005 there was much hype about how they can help a DBA keep their servers running in better health than ever before. This particular view gives an insight into the physical health of the indexes present in a database. Whether they are use or unused, complete or missing some columns is irrelevant, this is simply the physical stats of all indexes; disabled indexes are ignored however. In it’s simplest form this dmv can be executed as:   The results from executing this contain a record for every index in every database but some of the columns will be NULL. The first parameter is there so that you can specify which database you want to gather index details on, rather than scan every database. Simply specifying DB_ID() in place of the first NULL achieves this. In order to avoid the NULLS, or more accurately, in order to choose when to have the NULLS you need to specify a value for the last parameter. It takes one of 4 values – DEFAULT, ‘SAMPLED’, ‘LIMITED’ or ‘DETAILED’. If you execute the dmv with each of these values you can see some interesting details in the times taken to complete each step. DECLARE @Start DATETIME DECLARE @First DATETIME DECLARE @Second DATETIME DECLARE @Third DATETIME DECLARE @Finish DATETIME SET @Start = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, DEFAULT) AS ddips SET @First = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, 'SAMPLED') AS ddips SET @Second = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, 'LIMITED') AS ddips SET @Third = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, 'DETAILED') AS ddips SET @Finish = GETDATE() SELECT DATEDIFF(ms, @Start, @First) AS [DEFAULT] , DATEDIFF(ms, @First, @Second) AS [SAMPLED] , DATEDIFF(ms, @Second, @Third) AS [LIMITED] , DATEDIFF(ms, @Third, @Finish) AS [DETAILED] Running this code will give you 4 result sets; DEFAULT will have 12 columns full of data and then NULLS in the remainder. SAMPLED will have 21 columns full of data. LIMITED will have 12 columns of data and the NULLS in the remainder. DETAILED will have 21 columns full of data. So, from this we can deduce that the DEFAULT value (the same one that is also applied when you query the view using a NULL parameter) is the same as using LIMITED. Viewing the final result set has some details that are worth noting: Running queries against this view takes significantly longer when using the SAMPLED and DETAILED values in the last parameter. The duration of the query is directly related to the size of the database you are working in so be careful running this on big databases unless you have tried it on a test server first. Let’s look at the data we get back with the DEFAULT value first of all and then progress to the extra information later. We know that the first parameter that we supply has to be a database id and for the purposes of this blog we will be providing that value with the DB_ID function. We could just as easily put a fixed value in there or a function such as DB_ID (‘AnyDatabaseName’). The first columns we get back are database_id and object_id. These are pretty explanatory and we can wrap those in some code to make things a little easier to read: SELECT DB_NAME([ddips].[database_id]) AS [DatabaseName] , OBJECT_NAME([ddips].[object_id]) AS [TableName] … FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, NULL) AS ddips  gives us   SELECT DB_NAME([ddips].[database_id]) AS [DatabaseName] , OBJECT_NAME([ddips].[object_id]) AS [TableName], [i].[name] AS [IndexName] , ….. FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, NULL) AS ddips INNER JOIN [sys].[indexes] AS i ON [ddips].[index_id] = [i].[index_id] AND [ddips].[object_id] = [i].[object_id]     These handily tie in with the next parameters in the query on the dmv. If you specify an object_id and an index_id in these then you get results limited to either the table or the specific index. Once again we can place a  function in here to make it easier to work with a specific table. eg. SELECT * FROM [sys].[dm_db_index_physical_stats] (DB_ID(), OBJECT_ID(‘AdventureWorks2008.Person.Address’) , 1, NULL, NULL) AS ddips   Note: Despite me showing that functions can be placed directly in the parameters for this dmv, best practice recommends that functions are not used directly in the function as it is possible that they will fail to return a valid object ID. To be certain of not passing invalid values to this function, and therefore setting an automated process off on the wrong path, declare variables for the OBJECT_IDs and once they have been validated, use them in the function: DECLARE @db_id SMALLINT; DECLARE @object_id INT; SET @db_id = DB_ID(N’AdventureWorks_2008′); SET @object_id = OBJECT_ID(N’AdventureWorks_2008.Person.Address’); IF @db_id IS NULL BEGINPRINT N’Invalid database’; ENDELSE IF @object_id IS NULL BEGINPRINT N’Invalid object’; ENDELSE BEGINSELECT * FROM sys.dm_db_index_physical_stats (@db_id, @object_id, NULL, NULL , ‘LIMITED’); END; GO In cases where the results of querying this dmv don’t have any effect on other processes (i.e. simply viewing the results in the SSMS results area)  then it will be noticed when the results are not consistent with the expected results and in the case of this blog this is the method I have used. So, now we can relate the values in these columns to something that we recognise in the database lets see what those other values in the dmv are all about. The next columns are: We’ll skip partition_number, index_type_desc, alloc_unit_type_desc, index_depth and index_level  as this is a quick look at the dmv and they are pretty self explanatory. The final columns revealed by querying this view in the DEFAULT mode are avg_fragmentation_in_percent. This is the amount that the index is logically fragmented. It will show NULL when the dmv is queried in SAMPLED mode. fragment_count. The number of pieces that the index is broken into. It will show NULL when the dmv is queried in SAMPLED mode. avg_fragment_size_in_pages. The average size, in pages, of a single fragment in the leaf level of the IN_ROW_DATA allocation unit. It will show NULL when the dmv is queried in SAMPLED mode. page_count. Total number of index or data pages in use. OK, so what does this give us? Well, there is an obvious correlation between fragment_count, page_count and avg_fragment_size-in_pages. We see that an index that takes up 27 pages and is in 3 fragments has an average fragment size of 9 pages (27/3=9). This means that for this index there are 3 separate places on the hard disk that SQL Server needs to locate and access to gather the data when it is requested by a DML query. If this index was bigger than 72KB then having it’s data in 3 pieces might not be too big an issue as each piece would have a significant piece of data to read and the speed of access would not be too poor. If the number of fragments increases then obviously the amount of data in each piece decreases and that means the amount of work for the disks to do in order to retrieve the data to satisfy the query increases and this would start to decrease performance. This information can be useful to keep in mind when considering the value in the avg_fragmentation_in_percent column. This is arrived at by an internal algorithm that gives a value to the logical fragmentation of the index taking into account the multiple files, type of allocation unit and the previously mentioned characteristics if index size (page_count) and fragment_count. Seeing an index with a high avg_fragmentation_in_percent value will be a call to action for a DBA that is investigating performance issues. It is possible that tables will have indexes that suffer from rapid increases in fragmentation as part of normal daily business and that regular defragmentation work will be needed to keep it in good order. In other cases indexes will rarely become fragmented and therefore not need rebuilding from one end of the year to another. Keeping this in mind DBAs need to use an ‘intelligent’ process that assesses key characteristics of an index and decides on the best, if any, defragmentation method to apply should be used. There is a simple example of this in the sample code found in the Books OnLine content for this dmv, in example D. There are also a couple of very popular solutions created by SQL Server MVPs Michelle Ufford and Ola Hallengren which I would wholly recommend that you review for much further detail on how to care for your SQL Server indexes. Right, let’s get back on track then. Querying the dmv with the fifth parameter value as ‘DETAILED’ takes longer because it goes through the index and refreshes all data from every level of the index. As this blog is only a quick look a we are going to skate right past ghost_record_count and version_ghost_record_count and discuss avg_page_space_used_in_percent, record_count, min_record_size_in_bytes, max_record_size_in_bytes and avg_record_size_in_bytes. We can see from the details below that there is a correlation between the columns marked. Column 1 (Page_Count) is the number of 8KB pages used by the index, column 2 is how full each page is (how much of the 8KB has actual data written on it), column 3 is how many records are recorded in the index and column 4 is the average size of each record. This approximates to: ((Col1*8) * 1024*(Col2/100))/Col3 = Col4*. avg_page_space_used_in_percent is an important column to review as this indicates how much of the disk that has been given over to the storage of the index actually has data on it. This value is affected by the value given for the FILL_FACTOR parameter when creating an index. avg_record_size_in_bytes is important as you can use it to get an idea of how many records are in each page and therefore in each fragment, thus reinforcing how important it is to keep fragmentation under control. min_record_size_in_bytes and max_record_size_in_bytes are exactly as their names set them out to be. A detail of the smallest and largest records in the index. Purely offered as a guide to the DBA to better understand the storage practices taking place. So, keeping an eye on avg_fragmentation_in_percent will ensure that your indexes are helping data access processes take place as efficiently as possible. Where fragmentation recurs frequently then potentially the DBA should consider; the fill_factor of the index in order to leave space at the leaf level so that new records can be inserted without causing fragmentation so rapidly. the columns used in the index should be analysed to avoid new records needing to be inserted in the middle of the index but rather always be added to the end. * – it’s approximate as there are many factors associated with things like the type of data and other database settings that affect this slightly.  Another great resource for working with SQL Server DMVs is Performance Tuning with SQL Server Dynamic Management Views by Louis Davidson and Tim Ford – a free ebook or paperback from Simple Talk. Disclaimer – Jonathan is a Friend of Red Gate and as such, whenever they are discussed, will have a generally positive disposition towards Red Gate tools. Other tools are often available and you should always try others before you come back and buy the Red Gate ones. All code in this blog is provided “as is” and no guarantee, warranty or accuracy is applicable or inferred, run the code on a test server and be sure to understand it before you run it on a server that means a lot to you or your manager.

  Read the article

• Syncing between "kindle for PC" and "kindle for iPhone"

  - by Lou

  I have a number of ebooks that I am managing using calibre - E-book management. These books are in a number of various formats (pdf, chm, epub, mobi...etc). I found a blog post that detailed using calibre to convert the ebooks to ".mobi" versions and then, by double-clicking on the converted books, they would be added to my "kindle for PC" library. This worked very well. However, I can't seem to work out how to sync the books I've added to my "kindle for PC" library with my "kindle for iPhone" library. I should also mention that I do not own a kindle, all I'm trying to achieve is to be able to sync the books I've added to "kindle for PC" to "kindle for iPhone". Has anyone managed to do this? thanks.

  Read the article

• Can I configure a DNS cache not to forward AAAA queries?

  - by itsadok

  I'm setting up an internal DNS cache because my firewall is having trouble handling all the sessions created by DNS requests. I tried using bind9, dnsmasq and DJB dnscache, they all help reduce the number of requests leaving my network, but there are still a lot of request being made. Looking at the log files, and tcpdump and dnstop outputs, it seems that requests that return SERVFAIL do not get cached at all. And a lot of those failed requests are AAAA requests, which is a shame, because I do not have ipv6 enabled on any server. I've looked at several ways to help the situation, and I think if I could somehow prevent AAAA record requests from being forwarded by the DNS cache, it would reduce the number of requests significantly. The closest thing I found was the filter-aaaa-on-v4 option in BIND9. However, this only removes the record from the server response, and does not prevent it from forwarding it. Any help would be appreciated.

  Read the article

• Caching WCF javascript proxy on browser

  - by oazabir

  When you use WCF services from Javascript, you have to generate the Javascript proxies by hitting the Service.svc/js. If you have five WCF services, then it means five javascripts to download. As browsers download javascripts synchronously, one after another, it adds latency to page load and slows down page rendering performance. Moreover, the same WCF service proxy is downloaded from every page, because the generated javascript file is not cached on browser. Here is a solution that will ensure the generated Javascript proxies are cached on browser and when there is a hit on the service, it will respond with HTTP 304 if the Service.svc file has not changed. Here’s a Fiddler trace of a page that uses two WCF services. You can see there are two /js hits and they are sequential. Every visit to the same page, even with the same browser session results in making those two hits to /js. Second time when the same page is browsed: You can see everything else is cached, except the WCF javascript proxies. They are never cached because the WCF javascript proxy generator does not produce the necessary caching headers to cache the files on browser. Here’s an HttpModule for IIS and IIS Express which will intercept calls to WCF service proxy. It first checks if the service is changed since the cached version on the browser. If it has not changed then it will return HTTP 304 and not go through the service proxy generation process. Thus it saves some CPU on server. But if the request is for the first time and there’s no cached copy on browser, it will deliver the proxy and also emit the proper cache headers to cache the response on browser. http://www.codeproject.com/Articles/360437/Caching-WCF-javascript-proxy-on-browser Don’t forget to vote.

  Read the article

< Previous Page | 217 218 219 220 221 222 223 224 225 226 227 228  | Next Page >