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  • 11gr2 DataGuard: Restarting DUPLICATE After a Failure

    - by rene.kundersma
    One of the great new features that comes in very handy when databases get larger and larger these days is RMAN's capability to duplicate from an active database and even restart a duplicate when it fails. Imagine yourself the problem I had lately; I used the duplicate from active database feature and had to wait for an hour or 6 before all datafiles where transferred.At the end of the process some error occurred because of the syntax. While this error was easily to solve I was afraid I had to redo the complete procedure and transfer the 2.5 TB again. Well, 11gr2 RMAN surprised when I re-ran my command with the following output: Using previous duplicated file +DATA/fin2prod/datafile/users.2968.719237649 for datafile 12 with checkpoint SCN of 183289288148 Using previous duplicated file +DATA/fin2prod/datafile/users.2703.719237975 for datafile 13 with checkpoint SCN of 183289295823 Above I only show a small snippet, but what happend is that RMAN smartly skipped all files that where already transferred ! The documentation says this: RMAN automatically optimizes a DUPLICATE command that is a repeat of a previously failed DUPLICATE command. The repeat DUPLICATE command notices which datafiles were successfully copied earlier and does not copy them again. This applies to all forms of duplication, whether they are backup-based (with and without a target connection) or active database duplication. The automatic optimization of the DUPLICATE command can be especially useful when a failure occurs during the duplication of very large databases. If a DUPLICATE operation fails, you need only run the DUPLICATE again, using the same parameters contained in the original DUPLICATE command. Please see chapter 23 of the 11g Release 2 Database Backup and Recovery User's Guide for more details. B.w.t. be very careful with the duplicate command. A small mistake in one of the 'convert' parameters can potentially overwrite your target's controlfile without prompting ! Rene Kundersma Technical Architect Oracle Technology Services

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  • SPARC M7 Chip - 32 cores - Mind Blowing performance

    - by Angelo-Oracle
    The M7 Chip Oracle just announced its Next Generation Processor at the HotChips HC26 conference. As the Tech Lead in our Systems Division's Partner group, I had a front row seat to the extraordinary price performance advantage of Oracle current T5 and M6 based systems. Partner after partner tested  these systems and were impressed with it performance. Just read some of the quotes to see what our partner has been saying about our hardware. We just announced our next generation processor, the M7. This has 32 cores (up from 16-cores in T5 and 12-cores in M6). With 20 nm technology  this is our most advanced processor. The processor has more cores than anything else in the industry today. After the Sun acquisition Oracle has released 5 processors in 4 years and this is the 6th.  The S4 core  The M7 is built using the foundation of the S4 core. This is the next generation core technology. Like its predecessor, the S4 has 8 dynamic threads. It increases the frequency while maintaining the Pipeline depth. Each core has its own fine grain power estimator that keeps the core within its power envelop in 250 nano-sec granularity. Each core also includes Software in Silicon features for Application Acceleration Support. Each core includes features to improve Application Data Integrity, with almost no performance loss. The core also allows using part of the Virtual Address to store meta-data.  User-Level Synchronization Instructions are also part of the S4 core. Each core has 16 KB Instruction and 16 KB Data L1 cache. The Core Clusters  The cores on the M7 chip are organized in sets of 4-core clusters. The core clusters share  L2 cache.  All four cores in the complex share 256 KB of 4 way set associative L2 Instruction Cache, with over 1/2 TB/s of throughput. Two cores share 256 KB of 8 way set associative L2 Data Cache, with over 1/2 TB/s of throughput. With this innovative Core Cluster architecture, the M7 doubles core execution bandwidth. to maximize per-thread performance.  The Chip  Each  M7 chip has 8 sets of these core-clusters. The chip has 64 MB on-chip L3 cache. This L3 caches is shared among all the cores and is partitioned into 8 x 8 MB chunks. Each chunk is  8-way set associative cache. The aggregate bandwidth for the L3 cache on the chip is over 1.6TB/s. Each chip has 4 DDR4 memory controllers and can support upto 16 DDR4 DIMMs, allowing for 2 TB of RAM/chip. The chip also includes 4 internal links of PCIe Gen3 I/O controllers.  Each chip has 7 coherence links, allowing for 8 of these chips to be connected together gluelessly. Also 32 of these chips can be connected in an SMP configuration. A potential system with 32 chips will have 1024 cores and 8192 threads and 64 TB of RAM.  Software in Silicon The M7 chip has many built in Application Accelerators in Silicon. These features will be exposed to our Software partners using the SPARC Accelerator Program.  The M7  has built-in logic to decompress data at the speed of memory access. This means that applications can directly work on compressed data in memory increasing the data access rates. The VA Masking feature allows the use of part of the virtual address to store meta-data.  Realtime Application Data Integrity The Realtime Application Data Integrity feature helps applications safeguard against invalid, stale memory reference and buffer overflows. The first 4-bits if the Pointer can be used to store a version number and this version number is also maintained in the memory & cache lines. When a pointer accesses memory the hardware checks to make sure the two versions match. A SEGV signal is raised when there is a mismatch. This feature can be used by the Database, applications and the OS.  M7 Database In-Memory Query Accelerator The M7 chip also includes a In-Silicon Query Engines.  These accelerate tasks that work on In-Memory Columnar Vectors. Oracle In-Memory options stores data in Column Format. The M7 Query Engine can speed up In-Memory Format Conversion, Value and Range Comparisons and Set Membership lookups. This engine can work on Compressed data - this means not only are we accelerating the query performance but also increasing the memory bandwidth for queries.  SPARC Accelerated Program  At the Hotchips conference we also introduced the SPARC Accelerated Program to provide our partners and third part developers access to all the goodness of the M7's SPARC Application Acceleration features. Please get in touch with us if you are interested in knowing more about this program. 

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  • sftp to cygwin cmd fails with "received message too long"

    - by ana
    I have a windows server running cygwin, where open-ssh is set up. I am able to ssh into the server fine. I need to run a script that I cannot amend, and which needs to copy files via sftp, and requires the shell to be cmd. However, it fails with the message "received message too long" because when cmd starts it displays the Windows banner, and sftp chokes on this. I can't find any way to disable the banner, or redirect the output, or in any way get around this problem. Does anyone know how I can fix this?

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  • Slower wireless speed in Ubuntu 12.04 (64-bit) on Asus USB-N13

    - by PhantonTurtle
    I have an Asus USB-N13 which I use for wireless internet on my desktop. The download speed I get on Windows 7 (dual-boot) is 15.22 Mbps. On Ubuntu 12.04 (64-bit) I can only get 1.09 Mbps. I asked a question about this on the Ubuntu forums as well, but I did not get an answer. Here is the output from lsmod | grep rt which gives me, parport_pc 32866 0 rtl8192cu 103297 0 rtl8192c_common 75767 1 rtl8192cu rtlwifi 111202 1 rtl8192cu mac80211 506816 3 rtl8192cu,rtl8192c_common,rtlwifi cfg80211 205544 2 rtlwifi,mac80211 parport 46562 3 parport_pc,ppdev,lp I installed the drivers from Realtek (my chipset is Realtek, not Ralink) but that did not work.

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  • After upgrading to 12.04 the scanner from Brother Printer MFC-290C does not work

    - by Lorenzo
    I upgraded Ubuntu to 12.04 from 11.10. The printer works, but the scanner doesn't now. In 11.10 I had to install a special driver from Brother. The printer's model is Brother MFC-290C. The computer is a Toshiba Satellite. How can I get the scanner working? Update: I have a 64-bit installation on the Toshiba Satellite. Thank you for your instructions, Chad--24216. I followed each step: 1 through 5. I also updated the Brother Linux scanner S-KEY tool. The output of dpkg -l | grep Brother is: ii brscan-skey 0.2.3-0 Brother Linux scanner S-KEY tool ii brscan3 0.2.11-5 Brother Scanner Driver ii mfc290ccupswrapper:i386 1.1.2-2 Brother CUPS Inkjet Printer Definitions ii mfc290clpr:i386 1.1.2-2 Brother lpr Inkjet Printer Definitions ii printer-driver-ptouch 1.3-3ubuntu0.1 printer driver Brother P-touch label printers Still the scanner does not work. Here is the message from Xsane: Failed to open device brother3:bus6;dev1: Invalid argument. Here is the message from Simple Scan: Failed to scan. Unable to connect to scanner. And Scan Utility still doesn't display the scanner line.

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  • Cool SQL formatter tool

    - by AndyScott
    I have to deal with all types of code that was written by people from different organizations, different countries, using different languages, obviously standards are different across these sources.  One of the biggest headaches that I ahve come across is how people differ in the formatting of their SQL statements, specifically stored procs.  When you regularly get over 500 lines in a sproc, if the code is not formatted correctly, you can get lost trying to figure out where one nested BEGIN begins, and another nested END ends.  One of my co-workers showed me this site today that does a pretty damn good job of making sense of that type of code: http://www.dpriver.com/pp/sqlformat.htm.   This is a free website that offers a box to enter your nasty code, and click "Format SQL" and have it clean it for you.  I am sure that there are situations where this may not work, but given the code that I have been working with recently, it does a really good job.  There is a pay version with more options, including VS add-in, desktop component (with quickkeys to clean text in programs like notepad), the ability to output in HTML, and other stuff.  Heck, I watched a demo where the purchased version will take formatted SQL code and turn it into a generic Stringbuilder object embedded in a formatted. Yes, this seems like a shameless plug, but no, I have no relation/knowledge of anyone involved in the development of this product, it just seems useful.  Either way, I recommend checking out the free version.

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  • How do I recover from a Linux CentOS 4.6 Operating System Crash

    - by Greg Omebije
    Our x86 Linux server running CentOS4.6 has crashed. The machine boots only to the Grub prompt. We have tried using the "rescue mode" to recover the System, but it hasn't worked. How can we fix this problem, so that the machine boots normally? How can we fix this problem to the point were we can recover our files from the server Our Linux Server Configuration: Dell PowerEdge 1950 Intel Xeon 2 HDD (146GB each) 4GB RAM Hardware and Software raid setup CentOS 4.6 We used Sysrecord to boot the computer: the following are the output of fdisk -l Disk /dev/sda: 293.3 GB, 292326211584 255 heads, 63 sectors/track, 35539 Cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x00000080 Device Boot Start End Blocks Id System /dev/sda1 * 1 13 104391 83 Linux /dev/sda2 14 17769 142625070 8e Linux LVM

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  • How to change the screen resolution in VNC viewer for Ubuntu 12.04 without a monitor?

    - by user325320
    I have Ubuntu 12.04 installed on a machine and I always use it remotely from VNC. When I have monitor connected to this machine, I can change the resolution of my VNC viewer in the following line: $vnc4server --geometry 1440x900 This worked for me, but I always use this machine remotely, I unplug the monitor and reboot. and the above command line not work anymore. Then I tried xrandr SZ: Pixels Physical Refresh *0 1024 x 768 ( 260mm x 195mm ) *60 Current rotation - normal Current reflection - none Rotations possible - normal Reflections possible - none There is only one option available, so I tried to add a new one. $cvt 1440 900 # 1440x900 59.89 Hz (CVT 1.30MA) hsync: 55.93 kHz; pclk: 106.50 MHz Modeline "1440x900_60.00" 106.50 1440 1528 1672 1904 900 903 909 934 -hsync +vsync $xrandr --newmode "1440x900_60.00" 106.50 1440 1528 1672 1904 900 903 909 934 -hsync +vsync $xrandr --addmode S2 "1440x900_60.00" then I checked with xrandr again and can't see the new mode added. I try to execute the following command and get error says my RandR is too old. $xrandr --output S2 --mode 1440x900_60.00 xrandr: Server RandR version before 1.2 but this does not make sense to me, if I plug in the monitor back and run the xrandr command, it works again! It seems that Ubuntu must conntect to a real monitor before I can change my resolution in my VNC viewer. Can anyone help? UPDATE: Finally I solved this problem by changing to tightvncserver $tightvncserver -geometry 1440x900 works for me. Thanks everything answered my question

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  • Keeping file for personal use with GPG

    - by trixcit
    I have a small text file with personal (sensitve) information. I'm currently encrypting/decrypting it with the Makefile, as described on http://www.madboa.com/geek/gpg-quickstart/ ; relevant section is edit: @umask 0077;\ $(GPG) --output $(FILEPLAIN) --decrypt $(FILECRYPT) @emacs $(FILEPLAIN) @umask 0077;\ $(GPG) --encrypt --recipient $(GPGID) $(FILEPLAIN) @$(RM) $(FILEPLAIN) view: @umask 0077; $(GPG) --decrypt $(FILECRYPT) | less this works fine for viewing, but not for editting: I first have to enter my password, then edit the file, but to encrypt it afterwards I again have to enter my password twice (and it's a long one). Is there a better way to do this?

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  • How can I switch between the HDMI and DVI outputs of my graphics card?

    - by Owen Melbourne
    I've got an Nvidia GTX 560ti card which currently I've got my 2 monitors hooked up to using the 2 DVI ports. However its got a mini-HDMI port which I've plugged a HDMI cable in (with mini adapter) and lead it into my TV which is across the room. I'm hoping to be able to toggle between the HDMI output and the DVI outputs, however I'm not sure how I'd go about this, Could somebody please point me in the right direction, I'm not really worried about having all 3 on at the same time so that isn't a problem, but if its possible then I'll do that.

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  • Diagnosing xmodmap errors

    - by intuited
    I'm getting this error when trying to use xmodmap to get rid of caps lock: $ xmodmap -e 'clear Lock' X Error of failed request: BadValue (integer parameter out of range for operation) Major opcode of failed request: 118 (X_SetModifierMapping) Value in failed request: 0x17 Serial number of failed request: 8 Current serial number in output stream: 8 I'm running xfce on Maverick "10.10" Meercat. This problem did not occur before I added the Keyboard Layouts applet to a panel; before doing that, I was able to run my xmodmap script to swap Esc and CapsLock: !Remap Caps_Lock as Escape remove Lock = Caps_Lock keysym Caps_Lock = Escape It may be relevant that I chose alt-capslock as the keyboard switch combo in the Keyboard Layouts preferences. I've had a similar problem before, on a different machine, running openbox. On that machine, this problem started when I upgraded to Lucid, and has persisted in Maverick (release 10.10). I reported a bug in xorg. However, it remains unclear whether it's really a problem with xorg, or if I'm just doing something wrong with my configuration. Have other people experienced this problem? Can someone shed some light on what's going on here? It seems there are quite a few layers involved, and I don't understand any of them particularly well, so any information would be helpful. update I've discovered that the problem is specifically triggered by adding the Canada layout variant "Multilingual" (ca-multix). If I instead add the variant "Multilingual (first part)", the problem does not occur. I think this will probably end up being a usable workaround, but I don't yet know what the difference between these variants is. I've filed a freedesktop issue, and am commenting on a related ubuntu issue.

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  • Make Your Clock Creates a Custom Clock for your Android Homescreen

    - by ETC
    If you’d like to create a custom clock face your Android homescreen Make Your Clock makes it easy to create a clock face with customized colors, font, display style, and more. You can create a clock that looks like a digital watch face, an old fashioned flip clock, a combination of digital output and date, and other variations. You can also adjust the size of the clock to anywhere between 1×1 to 4×2. Currently the app is limited to displaying the time and date, future releases are slated to include weather and lunar phases in addition to the time. Check out the video below to see the app in action: Make Your Clock [AppBrain via Yahoo!] Latest Features How-To Geek ETC How To Remove People and Objects From Photographs In Photoshop Ask How-To Geek: How Can I Monitor My Bandwidth Usage? Internet Explorer 9 RC Now Available: Here’s the Most Interesting New Stuff Here’s a Super Simple Trick to Defeating Fake Anti-Virus Malware How to Change the Default Application for Android Tasks Stop Believing TV’s Lies: The Real Truth About "Enhancing" Images The Legend of Zelda – 1980s High School Style [Video] Suspended Sentence is a Free Cross-Platform Point and Click Game Build a Batman-Style Hidden Bust Switch Make Your Clock Creates a Custom Clock for your Android Homescreen Download the Anime Angels Theme for Windows 7 CyanogenMod Updates; Rolls out Android 2.3 to the Less Fortunate

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  • Refactoring an immediate drawing function into VBO, access violation error

    - by Alex
    I have a MD2 model loader, I am trying to substitute its immediate drawing function with a Vertex Buffer Object one.... I am getting a really annoying access violation reading error and I can't figure out why, but mostly I'd like an opinion as to whether this looks correct (never used VBOs before). This is the original function (that compiles ok) which calculates the keyframe and draws at the same time: glBegin(GL_TRIANGLES); for(int i = 0; i < numTriangles; i++) { MD2Triangle* triangle = triangles + i; for(int j = 0; j < 3; j++) { MD2Vertex* v1 = frame1->vertices + triangle->vertices[j]; MD2Vertex* v2 = frame2->vertices + triangle->vertices[j]; Vec3f pos = v1->pos * (1 - frac) + v2->pos * frac; Vec3f normal = v1->normal * (1 - frac) + v2->normal * frac; if (normal[0] == 0 && normal[1] == 0 && normal[2] == 0) { normal = Vec3f(0, 0, 1); } glNormal3f(normal[0], normal[1], normal[2]); MD2TexCoord* texCoord = texCoords + triangle->texCoords[j]; glTexCoord2f(texCoord->texCoordX, texCoord->texCoordY); glVertex3f(pos[0], pos[1], pos[2]); } } glEnd(); What I'd like to do is to calculate all positions before hand, store them in a Vertex array and then draw them. This is what I am trying to replace it with (in the exact same part of the program) int vCount = 0; for(int i = 0; i < numTriangles; i++) { MD2Triangle* triangle = triangles + i; for(int j = 0; j < 3; j++) { MD2Vertex* v1 = frame1->vertices + triangle->vertices[j]; MD2Vertex* v2 = frame2->vertices + triangle->vertices[j]; Vec3f pos = v1->pos * (1 - frac) + v2->pos * frac; Vec3f normal = v1->normal * (1 - frac) + v2->normal * frac; if (normal[0] == 0 && normal[1] == 0 && normal[2] == 0) { normal = Vec3f(0, 0, 1); } indices[vCount] = normal[0]; vCount++; indices[vCount] = normal[1]; vCount++; indices[vCount] = normal[2]; vCount++; MD2TexCoord* texCoord = texCoords + triangle->texCoords[j]; indices[vCount] = texCoord->texCoordX; vCount++; indices[vCount] = texCoord->texCoordY; vCount++; indices[vCount] = pos[0]; vCount++; indices[vCount] = pos[1]; vCount++; indices[vCount] = pos[2]; vCount++; } } totalVertices = vCount; glEnableClientState(GL_NORMAL_ARRAY); glEnableClientState(GL_TEXTURE_COORD_ARRAY); glEnableClientState(GL_VERTEX_ARRAY); glNormalPointer(GL_FLOAT, 0, indices); glTexCoordPointer(2, GL_FLOAT, sizeof(float)*3, indices); glVertexPointer(3, GL_FLOAT, sizeof(float)*5, indices); glDrawElements(GL_TRIANGLES, totalVertices, GL_UNSIGNED_BYTE, indices); glDisableClientState(GL_VERTEX_ARRAY); // disable vertex arrays glEnableClientState(GL_TEXTURE_COORD_ARRAY); glDisableClientState(GL_NORMAL_ARRAY); First of all, does it look right? Second, I get access violation error "Unhandled exception at 0x01455626 in Graphics_template_1.exe: 0xC0000005: Access violation reading location 0xed5243c0" pointing at line 7 Vec3f pos = v1->pos * (1 - frac) + v2->pos * frac; where the two Vs seems to have no value in the debugger.... Till this point the function behaves in exactly the same way as the one above, I don't understand why this happens? Thanks for any help you may be able to provide!

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  • Strange rsync behaviour

    - by Stewie
    So, I start with comparing two directories: [root@135759 ]# rsync -av test1/ test2/ building file list ... done sent 128 bytes received 20 bytes 296.00 bytes/sec total size is 6 speedup is 0.04 They both are in sync Now, let me create a file in test1 and copy it to test2 [root@135759 ]# touch test1/hello4.php [root@135759 ]# scp test1/hello4.php test2/hello4.php I verify that those are same: [root@135759 test2]# md5sum test1/hello4.php d41d8cd98f00b204e9800998ecf8427e hello4.php [root@135759 test1]# md5sum test2/hello4.php d41d8cd98f00b204e9800998ecf8427e hello4.php Thus, running rsync will show me 0 files. Why is the output not right ? [root@135759 ]# rsync -avn test1/ test2/ building file list ... done hello4.php sent 116 bytes received 24 bytes 280.00 bytes/sec total size is 6 speedup is 0.04

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  • Why lock-free data structures just aren't lock-free enough

    - by Alex.Davies
    Today's post will explore why the current ways to communicate between threads don't scale, and show you a possible way to build scalable parallel programming on top of shared memory. The problem with shared memory Soon, we will have dozens, hundreds and then millions of cores in our computers. It's inevitable, because individual cores just can't get much faster. At some point, that's going to mean that we have to rethink our architecture entirely, as millions of cores can't all access a shared memory space efficiently. But millions of cores are still a long way off, and in the meantime we'll see machines with dozens of cores, struggling with shared memory. Alex's tip: The best way for an application to make use of that increasing parallel power is to use a concurrency model like actors, that deals with synchronisation issues for you. Then, the maintainer of the actors framework can find the most efficient way to coordinate access to shared memory to allow your actors to pass messages to each other efficiently. At the moment, NAct uses the .NET thread pool and a few locks to marshal messages. It works well on dual and quad core machines, but it won't scale to more cores. Every time we use a lock, our core performs an atomic memory operation (eg. CAS) on a cell of memory representing the lock, so it's sure that no other core can possibly have that lock. This is very fast when the lock isn't contended, but we need to notify all the other cores, in case they held the cell of memory in a cache. As the number of cores increases, the total cost of a lock increases linearly. A lot of work has been done on "lock-free" data structures, which avoid locks by using atomic memory operations directly. These give fairly dramatic performance improvements, particularly on systems with a few (2 to 4) cores. The .NET 4 concurrent collections in System.Collections.Concurrent are mostly lock-free. However, lock-free data structures still don't scale indefinitely, because any use of an atomic memory operation still involves every core in the system. A sync-free data structure Some concurrent data structures are possible to write in a completely synchronization-free way, without using any atomic memory operations. One useful example is a single producer, single consumer (SPSC) queue. It's easy to write a sync-free fixed size SPSC queue using a circular buffer*. Slightly trickier is a queue that grows as needed. You can use a linked list to represent the queue, but if you leave the nodes to be garbage collected once you're done with them, the GC will need to involve all the cores in collecting the finished nodes. Instead, I've implemented a proof of concept inspired by this intel article which reuses the nodes by putting them in a second queue to send back to the producer. * In all these cases, you need to use memory barriers correctly, but these are local to a core, so don't have the same scalability problems as atomic memory operations. Performance tests I tried benchmarking my SPSC queue against the .NET ConcurrentQueue, and against a standard Queue protected by locks. In some ways, this isn't a fair comparison, because both of these support multiple producers and multiple consumers, but I'll come to that later. I started on my dual-core laptop, running a simple test that had one thread producing 64 bit integers, and another consuming them, to measure the pure overhead of the queue. So, nothing very interesting here. Both concurrent collections perform better than the lock-based one as expected, but there's not a lot to choose between the ConcurrentQueue and my SPSC queue. I was a little disappointed, but then, the .NET Framework team spent a lot longer optimising it than I did. So I dug out a more powerful machine that Red Gate's DBA tools team had been using for testing. It is a 6 core Intel i7 machine with hyperthreading, adding up to 12 logical cores. Now the results get more interesting. As I increased the number of producer-consumer pairs to 6 (to saturate all 12 logical cores), the locking approach was slow, and got even slower, as you'd expect. What I didn't expect to be so clear was the drop-off in performance of the lock-free ConcurrentQueue. I could see the machine only using about 20% of available CPU cycles when it should have been saturated. My interpretation is that as all the cores used atomic memory operations to safely access the queue, they ended up spending most of the time notifying each other about cache lines that need invalidating. The sync-free approach scaled perfectly, despite still working via shared memory, which after all, should still be a bottleneck. I can't quite believe that the results are so clear, so if you can think of any other effects that might cause them, please comment! Obviously, this benchmark isn't realistic because we're only measuring the overhead of the queue. Any real workload, even on a machine with 12 cores, would dwarf the overhead, and there'd be no point worrying about this effect. But would that be true on a machine with 100 cores? Still to be solved. The trouble is, you can't build many concurrent algorithms using only an SPSC queue to communicate. In particular, I can't see a way to build something as general purpose as actors on top of just SPSC queues. Fundamentally, an actor needs to be able to receive messages from multiple other actors, which seems to need an MPSC queue. I've been thinking about ways to build a sync-free MPSC queue out of multiple SPSC queues and some kind of sign-up mechanism. Hopefully I'll have something to tell you about soon, but leave a comment if you have any ideas.

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  • Haskell Parse Paragraph and em element with Parsec

    - by Tincho
    I'm using Text.ParserCombinators.Parsec and Text.XHtml to parse an input like this: this is the beginning of the paragraph --this is an emphasized text-- and this is the end\n And my output should be: <p>this is the beginning of the paragraph <em>this is an emphasized text</em> and this is the end\n</p> This code parses and returns an emphasized element em = do{ ;count 2 (char '-') ; ;s <- manyTill anyChar (count 2 (char '-')) ;return (emphasize << s) } But I don't know how to get the paragraphs with emphasized items Any ideas? Thanks!!

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  • Laptop battery: is voltage really important to respect?

    - by Marc-Andre R.
    I got an Acer Aspire 5100 and I just bought a new battery (after the stock battery just died yesterday). But I saw something after buying and I'm wondering whether it's really important or not. My stock battery was a 6-cell 4000mah 11.1v and the new battery is an 8-cell 4800mah 14.8v . I know that 8-cell and 4800mah is okay, but what about the 14.8v instead of 11.1v? The battery description says it's compatible with my laptop model (AS5100, model BL51), but the voltage difference makes me wonder. Will the laptop only take what it needs? Or will it be getting 14.8v straight in the brain? I know that my wall plug claims to output 19v, so logically I'm thinking a higher voltage battery shouldn't be a problem. Am I correct in thinking this? Thanks in advance for your answers!

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  • Synergy: server refused client

    - by Tom
    I am trying to get Synergy up and running from a new Windows 7 computer, to an XP computer. The Synergy installations seemed to go fine. I configured each to start on start-up, which they seem to, but the client won't connect. I get repeated: "server refused client with our name" messages in the log output. The Synergy FAQ says to "Add the client to the server's configuration file." But I can't seem to find an instruction set on how to do this. I've looked and looked, but I'm lost...

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  • tcpdump selective acknowledgements question

    - by wlaus
    Hi All, I eventually sometimes watch most initial tcp connection attempts like this: tcpdump -nn -Z somepcapuser not src host (12x.x5.109.xxx or 62.75.160.xxx ) and not (port 9001 or 443 or 8080 ) and tcp[tcpflags]&(tcp-syn) !=0 and not tcp[tcpflags]& (tcp-ack) !=0 or icmp this works pretty well to quickly identify oddness so far. However, I now have a question on the following output: 03:53:52.227884 IP 203.81.166.20.53786 62.75.160.xxx.80: S 846930886:846930886(0) win 61690 "<"mss 1460,nop,nop,sackOK,opt-178:f04700000000,nop,wscale 4"" I wonder what the marked portion means, haven't seen that before. Thanks for help wlaus

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  • Using Oracle Receivables Diagnostics: How To Run, Read & Use To Troubleshoot

    - by Robert Story
    Upcoming WebcastTitle: Using Oracle Receivables Diagnostics: How To Run, Read & Use To TroubleshootDate: March 31, 2010 Time: 10:00 am EDT Product Family: Receivables Community Summary This one-hour session is recommended for functional users who want to take a more active role in the generation of Diagnostics in Oracle Receivables. This session will provide an overview of how diagnostics are structured and give some tips on how to read/analyze the output as well as some simple troubleshooting tips. Topics will include: Review of Diagnostic Catalogs in Release 11i, 12.0.x and 12.1.1How to run some of the more popular Receivables DiagnosticsHow to read and analyze diagnostic data Examine the log viewer A short, live demonstration (only if applicable) and question and answer period will be included. Click here to register for this session....... ....... ....... ....... ....... ....... .......The above webcast is a service of the E-Business Suite Communities in My Oracle Support.For more information on other webcasts, please reference the Oracle Advisor Webcast Schedule.Click here to visit the E-Business Communities in My Oracle Support Note that all links require access to My Oracle Support.

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  • What is causing my spacebar to randomly stop working?

    - by Chris Billington
    A couple of times a day, I'll be typing something and realise I can't type spaces. Usually the cursor will flicker instead when I press the spacebar, and I can type all other letters as far as I can tell. If I'm in a terminal the cursor turns from a solid square to an empty square until I release the spacebar. For some reason, restarting compiz with alt-F2 compiz fixes it, until it next occurs. I can still copy and paste spaces from sources that already have them, and I can still insert spaces with ctrl-shift-u, 20, enter. This has been happening for a while, since before I upgraded to maverick, but it feels like its beceoming more frequent. There really doesn't seem to be any kind of a pattern to it. I'm using 64 bit ubuntu 10.10 on a system76 panp7 laptop. Any ideas how I might troubleshoot? EDIT: using xev, normally a spacebar registers as: KeyPress event, serial 36, synthetic NO, window 0x5600001, root 0x101, subw 0x0, time 26488647, (88,403), root:(748,458), state 0x10, keycode 65 (keysym 0x20, space), same_screen YES, XLookupString gives 1 bytes: (20) " " XmbLookupString gives 1 bytes: (20) " " XFilterEvent returns: False KeyRelease event, serial 36, synthetic NO, window 0x5600001, root 0x101, subw 0x0, time 26488729, (88,403), root:(748,458), state 0x10, keycode 65 (keysym 0x20, space), same_screen YES, XLookupString gives 1 bytes: (20) " " XFilterEvent returns: False But when it's stopped behaving a press of the spacebar instead gives the three events: FocusOut event, serial 36, synthetic NO, window 0x5600001, mode NotifyGrab, detail NotifyAncestor FocusIn event, serial 36, synthetic NO, window 0x5600001, mode NotifyUngrab, detail NotifyAncestor KeymapNotify event, serial 36, synthetic NO, window 0x0, keys: 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 FURTHER EDIT: Ok, so I think I've solved the problem, and by that I mean I now know which package to file a bug against. I have a hot corner which initiates a window picker, and I've customised the window picking so that left click goes to a window, right click closes one and spacebar zooms in on one. When I go to this hot corner, compiz must take control of my spacebar, and clearly isn't giving it back when I leave the window picker. So I'll be filing a bug against compiz. reported:here

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  • Mac OS ? Assembly Language Esoteria

    - by veryfoolish
    I've been playing around with assembly and object files in general on Mac OS ? and was wondering if somebody could provide some edification. Specifically, I'm wondering what the extra code GCC generates when compiling the C file in the following example does. I have a toy C program so I can comprehend the assembly output. int main() { int a = 5; int b = 5; int c = a + b; } Running this through gcc -S creates the following assembly: .text .globl _main _main: LFB2: pushq %rbp LCFI0: movq %rsp, %rbp LCFI1: movl $5, -4(%rbp) movl $5, -8(%rbp) movl -8(%rbp), %eax addl -4(%rbp), %eax movl %eax, -12(%rbp) leave ret LFE2: .section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support EH_frame1: .set L$set$0,LECIE1-LSCIE1 .long L$set$0 LSCIE1: .long 0x0 .byte 0x1 .ascii "zR\0" .byte 0x1 .byte 0x78 .byte 0x10 .byte 0x1 .byte 0x10 .byte 0xc .byte 0x7 .byte 0x8 .byte 0x90 .byte 0x1 .align 3 LECIE1: .globl _main.eh _main.eh: LSFDE1: .set L$set$1,LEFDE1-LASFDE1 .long L$set$1 LASFDE1: .long LASFDE1-EH_frame1 .quad LFB2-. .set L$set$2,LFE2-LFB2 .quad L$set$2 .byte 0x0 .byte 0x4 .set L$set$3,LCFI0-LFB2 .long L$set$3 .byte 0xe .byte 0x10 .byte 0x86 .byte 0x2 .byte 0x4 .set L$set$4,LCFI1-LCFI0 .long L$set$4 .byte 0xd .byte 0x6 .align 3 LEFDE1: .subsections_via_symbols The LCFI1 section seems to contain the actual logic for the program, but I'm not sure what the misc. other stuff is for... also, is there any scheme these labels are following? I'm sorry this is such a vague question. I'd appreciate anything, including being pointed to a resource where I can find out more about this. Thanks!

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  • Why do Finder and du report different file size?

    - by flipdoubt
    I am writing a geektool 3 script to show the size of a particular VMware Fusion virtual machine. Get Info in Finder says the file is "52.91 GB". I run the following du command to get the file size: > du -hs ~/Documents/Virtual\ Machines.localized/MY-PRECIOUS-7.vmwarevm | awk '{print $1}' This du -hs command returns the file size as "49G". What accounts for the difference from what Finder reports? Alternatively, I have tried replacing the -s option with the -d option like so: du -hd ~/Documents/Virtual\ Machines.localized/MY-PRECIOUS-7.vmwarevm | awk '{print $1}' This du -hd command returns the file size as "59G". What accounts for the difference between Finder, du -hd, and du -hs? Also, this du -hd command produces no output in geektool 3. What gives?

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  • How to tell if SPARC T4 crypto is being used?

    - by danx
    A question that often comes up when running applications on SPARC T4 systems is "How can I tell if hardware crypto accleration is being used?" To review, the SPARC T4 processor includes a crypto unit that supports several crypto instructions. For hardware crypto these include 11 AES instructions, 4 xmul* instructions (for AES GCM carryless multiply), mont for Montgomery multiply (optimizes RSA and DSA), and 5 des_* instructions (for DES3). For hardware hash algorithm optimization, the T4 has the md5, sha1, sha256, and sha512 instructions (the last two are used for SHA-224 an SHA-384). First off, it's easy to tell if the processor T4 crypto instructions—use the isainfo -v command and look for "sparcv9" and "aes" (and other hash and crypto algorithms) in the output: $ isainfo -v 64-bit sparcv9 applications crc32c cbcond pause mont mpmul sha512 sha256 sha1 md5 camellia kasumi des aes ima hpc vis3 fmaf asi_blk_init vis2 vis popc These instructions are not-privileged, so are available for direct use in user-level applications and libraries (such as OpenSSL). Here is the "openssl speed -evp" command shown with the built-in t4 engine and with the pkcs11 engine. Both run the T4 AES instructions, but the t4 engine is faster than the pkcs11 engine because it has less overhead (especially for smaller packet sizes): t-4 $ /usr/bin/openssl version OpenSSL 1.0.0j 10 May 2012 t-4 $ /usr/bin/openssl engine (t4) SPARC T4 engine support (dynamic) Dynamic engine loading support (pkcs11) PKCS #11 engine support t-4 $ /usr/bin/openssl speed -evp aes-128-cbc # t4 engine used by default . . . The 'numbers' are in 1000s of bytes per second processed. type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes aes-128-cbc 487777.10k 816822.21k 986012.59k 1017029.97k 1053543.08k t-4 $ /usr/bin/openssl speed -engine pkcs11 -evp aes-128-cbc engine "pkcs11" set. . . . The 'numbers' are in 1000s of bytes per second processed. type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes aes-128-cbc 31703.58k 116636.39k 350672.81k 696170.50k 993599.49k Note: The "-evp" flag indicates use the OpenSSL "EnVeloPe" API, which gives more accurate results. That's because it tells OpenSSL to use the same API that external programs use when calling OpenSSL libcrypto functions, evp(3openssl). DTrace Shows if T4 Crypto Functions Are Used OK, good enough, the isainfo(1) command shows the instructions are present, but how does one know if they are being used? Chi-Chang Lin, who works on Oracle Solaris performance, wrote a Dtrace script to show if T4 instructions are being executed. To show the T4 instructions are being used, run the following Dtrace script. Look for functions named "t4" and "yf" in the output. The OpenSSL T4 engine uses functions named "t4" and the PKCS#11 engine uses functions named "yf". To demonstrate, I'll first run "openssl speed" with the built-in t4 engine then with the pkcs11 engine. The performance numbers are not valid due to dtrace probes slowing things down. t-4 # dtrace -Z -n ' pid$target::*yf*:entry,pid$target::*t4_*:entry{ @[probemod, probefunc] = count();}' \ -c "/usr/bin/openssl speed -evp aes-128-cbc" dtrace: description 'pid$target::*yf*:entry' matched 101 probes . . . dtrace: pid 2029 has exited libcrypto.so.1.0.0 ENGINE_load_t4 1 libcrypto.so.1.0.0 t4_DH 1 libcrypto.so.1.0.0 t4_DSA 1 libcrypto.so.1.0.0 t4_RSA 1 libcrypto.so.1.0.0 t4_destroy 1 libcrypto.so.1.0.0 t4_free_aes_ctr_NIDs 1 libcrypto.so.1.0.0 t4_init 1 libcrypto.so.1.0.0 t4_add_NID 3 libcrypto.so.1.0.0 t4_aes_expand128 5 libcrypto.so.1.0.0 t4_cipher_init_aes 5 libcrypto.so.1.0.0 t4_get_all_ciphers 6 libcrypto.so.1.0.0 t4_get_all_digests 59 libcrypto.so.1.0.0 t4_digest_final_sha1 65 libcrypto.so.1.0.0 t4_digest_init_sha1 65 libcrypto.so.1.0.0 t4_sha1_multiblock 126 libcrypto.so.1.0.0 t4_digest_update_sha1 261 libcrypto.so.1.0.0 t4_aes128_cbc_encrypt 1432979 libcrypto.so.1.0.0 t4_aes128_load_keys_for_encrypt 1432979 libcrypto.so.1.0.0 t4_cipher_do_aes_128_cbc 1432979 t-4 # dtrace -Z -n 'pid$target::*yf*:entry{ @[probemod, probefunc] = count();}   pid$target::*yf*:entry,pid$target::*t4_*:entry{ @[probemod, probefunc] = count();}' \ -c "/usr/bin/openssl speed -engine pkcs11 -evp aes-128-cbc" dtrace: description 'pid$target::*yf*:entry' matched 101 probes engine "pkcs11" set. . . . dtrace: pid 2033 has exited libcrypto.so.1.0.0 ENGINE_load_t4 1 libcrypto.so.1.0.0 t4_DH 1 libcrypto.so.1.0.0 t4_DSA 1 libcrypto.so.1.0.0 t4_RSA 1 libcrypto.so.1.0.0 t4_destroy 1 libcrypto.so.1.0.0 t4_free_aes_ctr_NIDs 1 libcrypto.so.1.0.0 t4_get_all_ciphers 1 libcrypto.so.1.0.0 t4_get_all_digests 1 libsoftcrypto.so.1 rijndael_key_setup_enc_yf 1 libsoftcrypto.so.1 yf_aes_expand128 1 libcrypto.so.1.0.0 t4_add_NID 3 libsoftcrypto.so.1 yf_aes128_cbc_encrypt 1542330 libsoftcrypto.so.1 yf_aes128_load_keys_for_encrypt 1542330 So, as shown above the OpenSSL built-in t4 engine executes t4_* functions (which are hand-coded assembly executing the T4 AES instructions) and the OpenSSL pkcs11 engine executes *yf* functions. Programmatic Use of OpenSSL T4 engine The OpenSSL t4 engine is used automatically with the /usr/bin/openssl command line. Chi-Chang Lin also points out that if you're calling the OpenSSL API (libcrypto.so) from a program, you must call ENGINE_load_built_engines(), otherwise the built-in t4 engine will not be loaded. You do not call ENGINE_set_default(). That's because "openssl speed -evp" test calls ENGINE_load_built_engines() even though the "-engine" option wasn't specified. OpenSSL T4 engine Availability The OpenSSL t4 engine is available with Solaris 11 and 11.1. For Solaris 10 08/11 (U10), you need to use the OpenSSL pkcs311 engine. The OpenSSL t4 engine is distributed only with the version of OpenSSL distributed with Solaris (and not third-party or self-compiled versions of OpenSSL). The OpenSSL engine implements the AES cipher for Solaris 11, released 11/2011. For Solaris 11.1, released 11/2012, the OpenSSL engine adds optimization for the MD5, SHA-1, and SHA-2 hash algorithms, and DES-3. Although the T4 processor has Camillia and Kasumi block cipher instructions, these are not implemented in the OpenSSL T4 engine. The following charts may help view availability of optimizations. The first chart shows what's available with Solaris CLIs and APIs, the second chart shows what's available in Solaris OpenSSL. Native Solaris Optimization for SPARC T4 This table is shows Solaris native CLI and API support. As such, they are all available with the OpenSSL pkcs11 engine. CLIs: "openssl -engine pkcs11", encrypt(1), decrypt(1), mac(1), digest(1), MD5sum(1), SHA1sum(1), SHA224sum(1), SHA256sum(1), SHA384sum(1), SHA512sum(1) APIs: PKCS#11 library libpkcs11(3LIB) (incluDES Openssl pkcs11 engine), libMD(3LIB), and Solaris kernel modules AlgorithmSolaris 1008/11 (U10)Solaris 11Solaris 11.1 AES-ECB, AES-CBC, AES-CTR, AES-CBC AES-CFB128 XXX DES3-ECB, DES3-CBC, DES2-ECB, DES2-CBC, DES-ECB, DES-CBC XXX bignum Montgomery multiply (RSA, DSA) XXX MD5, SHA-1, SHA-256, SHA-384, SHA-512 XXX SHA-224 X ARCFOUR (RC4) X Solaris OpenSSL T4 Engine Optimization This table is for the Solaris OpenSSL built-in t4 engine. Algorithms listed above are also available through the OpenSSL pkcs11 engine. CLI: openssl(1openssl) APIs: openssl(5), engine(3openssl), evp(3openssl), libcrypto crypto(3openssl) AlgorithmSolaris 11Solaris 11SRU2Solaris 11.1 AES-ECB, AES-CBC, AES-CTR, AES-CBC AES-CFB128 XXX DES3-ECB, DES3-CBC, DES-ECB, DES-CBC X bignum Montgomery multiply (RSA, DSA) X MD5, SHA-1, SHA-256, SHA-384, SHA-512 XX SHA-224 X Source Code Availability Solaris Most of the T4 assembly code that called the new T4 crypto instructions was written by Ferenc Rákóczi of the Solaris Security group, with assistance from others. You can download the Solaris source for this and other parts of Solaris as a few zip files at the Oracle Download website. The relevant source files are generally under directories usr/src/common/crypto/{aes,arcfour,des,md5,modes,sha1,sha2}}/sun4v/. and usr/src/common/bignum/sun4v/. Solaris 11 binary is available from the Oracle Solaris 11 download website. OpenSSL t4 engine The source for the OpenSSL t4 engine, which is based on the Solaris source above, is viewable through the OpenGrok source code browser in directory src/components/openssl/openssl-1.0.0/engines/t4 . You can download the source from the same website or through Mercurial source code management, hg(1). Conclusion Oracle Solaris with SPARC T4 provides a rich set of accelerated cryptographic and hash algorithms. Using the latest update, Solaris 11.1, provides the best set of optimized algorithms, but alternatives are often available, sometimes slightly slower, for releases back to Solaris 10 08/11 (U10). Reference See also these earlier blogs. SPARC T4 OpenSSL Engine by myself, Dan Anderson (2011), discusses the Openssl T4 engine and reviews the SPARC T4 processor for the Solaris 11 release. Exciting Crypto Advances with the T4 processor and Oracle Solaris 11 by Valerie Fenwick (2011) discusses crypto algorithms that were optimized for the T4 processor with the Solaris 11 FCS (11/11) and Solaris 10 08/11 (U10) release. T4 Crypto Cheat Sheet by Stefan Hinker (2012) discusses how to make T4 crypto optimization available to various consumers (such as SSH, Java, OpenSSL, Apache, etc.) High Performance Security For Oracle Database and Fusion Middleware Applications using SPARC T4 (PDF, 2012) discusses SPARC T4 and its usage to optimize application security. Configuring Oracle iPlanet WebServer / Oracle Traffic Director to use crypto accelerators on T4-1 servers by Meena Vyas (2012)

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  • SSH via DHCP server

    - by SFault
    I have a DHCP server setup and I can't seem to connect to anything through SSH. When I'm logged in to the server itself, I can SSH. But when I connect any machine to the DHCP server, that machine can SSH but every server I SSH to asks for a password when the normal behavior (when not connected to the DHCP server) does not. Here are the contents of my iptables script that are related to port 22. $IPT -t nat -A PREROUTING -i $LAN -p tcp --dport 22 -j REDIRECT --to-port 22 $IPT -A FORWARD -i $LAN -p tcp --dport 22 -j ACCEPT $IPT -A INPUT -i $LAN -p tcp --dport 22 -j ACCEPT $IPT -A INPUT -i $WAN -p tcp --dport 22 -j ACCEPT $IPT -A OUTPUT -p tcp --sport 22 -m state --state ESTABLISHED -j ACCEPT $IPT -A INPUT -i $LAN -p tcp --dport 22 -m state --state NEW,ESTABLISHED -j ACCEPT Am I missing something?

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