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  • MsMpEng.exe (Windows Defender?) uses a lot of CPU at startup and runs two instances on a single core

    - by dlamblin
    I'm using Windows XP Professional SP2 on a single core AMD64 processor, and I've got two instances of MsMpEng.exe starting up when I start up and log in. They use 64MB and 32MB of ram and 140MB and 80MB of virtual memory, and fluctuate around 80% CPU usage for about 5 minutes at start up. They are (I read) associated with Windows Defender, but I'm concerned about: There's two of them, everything I read generally has only one reported. They might be scanning each other, and I want that to stop. They might be getting scanned by avgrsx.exe (AVG Free 8) (uses about 16Mb v ram) They might also be scanning moe.exe (assosciated with ms live mesh, which I'm considering getting rid of) Lastly I have Microsoft Security Essentials. I don't know the process name associated there. The main concern of mine (apart from the double instances) is that these are all trying to prioritize scanning each other at once except maybe moe.exe. This might seem legitimate but is likely a useless drain on resources. Have I made a mistake in having all of these installed, or is there a way to inform them not to do whatever they're doing that's taking about 5+ minutes at start up? [I also have Google Desktop, but I'm keeping that.] Comment if none of this makes sense to you.

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  • Windows shutting down, CPU maxing out in Windows-7 32-bit? [closed]

    - by Vivek Sharma
    I have no idea, what is happening to my laptop. For last 5-6 times it has automatically shutdown while running, without doing anything serious. And I even do get the message during boot which says - Start windows normal - Start in safe mode It just boots up normal. Few days ago, my screen blinked and it the PC shutdown immediately. After that I was not able to get it started. I got it repaired, the guy said he has replaced the display chip (nVidia-nvs-140), but i seriously doubt that. Now it started working, but would shutdown every 20 mins or so. I have a dual boot, ubuntu-11.10 works just fine. Virus scan on windows shows nothing. I am pasting my perfmon output. My CPU for reason is maxing out to 100% continously, for windows internal processes. Please have a look at the attached file. Strangly now for last 2 hours it is working fine, but i am just writing emails and reading excels. ThinkPad T61 | t9300 | 3gb | nVidia 140 nvs-quadro (latest driver 296.10) What do you suggest?

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  • Merely installing PHP5 causes my AWS Ubuntu server to die minutes later from a massive CPU spike

    - by Mark Amery
    I have an AWS server with Ubuntu 11.04 as the OS that is running an Apache2 webserver (incidentally Python-based and using Django). We recently needed to add support for php5 to let us use a third party PHP library (incidentally for serving minified versions of js and css files). However, for no reason any of us can discern, if we simply run sudo apt-get install php5 on the server, then the install appears to finish successfully but, without us taking any further action (including not yet running sudo apt-get install libapache2-mod-php5, which I think would be the next step for us if everything worked), or actually running any PHP scripts on the server, a few minutes later the server becomes impossible to connect to, and looking at the 'Monitoring' tab for the server in the EC2 Management Console reveals that a while after the installation, CPU usage spikes to 100% and stays there permanently (until we reboot the server from the AWS Console). After rebooting, the server also reliably dies within a few (between 0 and 10) minutes. We restored the server to a pre-PHP state from an AMI Image, observed that it was stable, and then tried installing PHP5 again and observed the server die in exactly the same way, so we're pretty much certain that installing PHP5 is what causes the symptoms. What on earth could be causing this behaviour, and how can we get PHP installed on the server without it dying?

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  • How to keep the CPU usage down while running an SDL program?

    - by budwiser
    I've done a very basic window with SDL and want to keep it running until I press the X on window. #include "SDL.h" const int SCREEN_WIDTH = 640; const int SCREEN_HEIGHT = 480; int main(int argc, char **argv) { SDL_Init( SDL_INIT_VIDEO ); SDL_Surface* screen = SDL_SetVideoMode( SCREEN_WIDTH, SCREEN_HEIGHT, 0, SDL_HWSURFACE | SDL_DOUBLEBUF ); SDL_WM_SetCaption( "SDL Test", 0 ); SDL_Event event; bool quit = false; while (quit != false) { if (SDL_PollEvent(&event)) { if (event.type == SDL_QUIT) { quit = true; } } SDL_Delay(80); } SDL_Quit(); return 0; } I tried adding SDL_Delay() at the end of the while-clause and it worked quite well. However, 80 ms seemed to be the highest value I could use to keep the program running smoothly and even then the CPU usage is about 15-20%. Is this the best way to do this and do I have to just live with the fact that it eats this much CPU already on this point?

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  • SPARC T4 ?????????

    - by user12798668
    ????????????????????????????????????????????????????? SPARC T4 ????????????????????????????T4 ??????? SP(Service Processor) ??? ILOM ?? - set /SP/powermgmt policy=elastic ?????????????????????????????????????????????????????????????????????????????????????????ILOM ? /SYS/VSP/history/0 ???????????????????????????? SPARC T4-1 ? OS ??????????????????????????????????????????????????????????? ?? ?? = ?????(W)?????????????? Mar 26 12:04:54 = 294 Mar 26 12:03:53 = 292 Mar 26 12:02:53 = 292 Mar 26 12:01:53 = 293 Mar 26 12:00:53 = 292 Mar 26 11:59:53 = 293 Mar 26 11:58:54 = 293 Mar 26 11:57:54 = 294 Mar 26 11:56:54 = 293 Mar 26 11:55:54 = 348 ????????????????????? 90W ?????????! ?? psrinfo ????????????????... # psrinfo 0 on-line since 03/23/2012 17:39:28 1 on-line since 03/26/2012 20:53:56 ?? SPARC T4-1 ????????8 ????????? 8 CPU ??????? SPARC T4 CPU ? 1 ??????????????psrinfo ??????? 64 CPU ??? OS ?????????????????????? 2 CPU ??????????! ???????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????CPU ??????????????????????????????????????????????????????????????????????????????????????????????????????? 2 CPU ?????????????????????????????????? CPU ????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? ??????????? SPARC T4 ????????????? Oracle VM Server for SPARC (OVM for SPARC) ?????????????????????????????????????????????????? Oracle VM Server for SPARC ???????????? ?10? ??????? - ??????? ??????????????????????????OTN ? How to Use the Power Management Controls on SPARC Servers ?????????????????????????????? ??????????????SPARC T4 ?????????????????? Oracle OpenWorld Tokyo 2012 ???????????????????? ?????????????????????????·????????????????????! 4/4(?) ???? K1-01?ENGINEERED FOR INNOVATION ???????????????(9:00-11:15) 4/5(?) ????????? G2-01 ???????&???????????IT???????????(11:50 - 13:20) ???????????!! Oracle OpenWorld Tokyo 2012 ???? URL http://www.oracle.com/openworld/jp-ja/index.html ?????? 7264 ???????????????

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  • ???TCO?????????!? WebLogic Server vs. JBoss Enterprise Application Platform

    - by Tatsuhiro Yamaguchi
    WebLogic Server?????????????Java EE??????????·?????JBoss Enterprise Application Platform(EAP)????????????????WebLogic Server?????????JBoss EAP????????????????????????????????????????TCO(??????)???????????...?????????????????????????1?????????????????????????????????TCO?JBoss EAP??WebLogic Server??????????????????????(???) ????????????????????????WebLogic Server??Java????????????? Java EE??????????·???????????WebLogic Server????????????????????·?????????????????????JBoss EAP??JBoss EAP?????????????????????·??????????????????????????????????????????????????????????????????? ????????·?????????????????????????????????1?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? ?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? ????????????????Java??????????????????????????Java SE 6?????????????2013?2????????????????????????????????????????? ?????? Java SE 6????????????????(Oracle Technology Network) ???????????????JBoss EAP 5????Java SE 6??????????2013?2??????????????????????????????????????? ?????2012?8????????????JBoss EAP 6????????? ????Java SE 7?????????Java SE 7?????????????2014?7??????????JBoss EAP 6????????????2013??????????????????????????????Java SE 7???????????????1????????????????????????????Java SE 7????????????????????Java SE??????????????????????????????? ???????WebLogic Server??????????????????Java SE???????????????????Java SE 6?2016?12????Java SE 7?????2019?7???????????????????????????????????????????WebLogic Server????????????????????????????????Java SE??????????? JBoss EAP?????????????????Java SE????????????Java SE???????????????????????WebLogic Server??????????????????JBoss EAP?????????????????????????????????? ??????????????????WebLogic Server?????????????????? ??????????????????JBoss EAP?WebLogic Server????????????1????????????????WebLogic Server????????????????????????????????????????????????????????????????? ???JBoss EAP?????????????????????????????????????????????????????????????????????????????????????????WebLogic Server??????????????????????? ?????????????????????????????????????????????WebLogic Server?JBoss EAP?????????????????????????????????????????????????????????????????????????????????????????????????????WebLogic Server?JBoss EAP????????????? ??????????????? 3~6????????WebLogic Server????????????????????????WebLogic Server??? ??????????????????????????????????????????????????? JBoss EAP??2????????????24??365????????????Premium?????(??~??)9?~5????????????Standard??????????????????????????(CPU?????????????16??)???????????6???????????????????? · JBoss EAP Standard · JBoss EAP Premium » ???????:?0 » ???????:?0 » ??????:?85?/1?? » ??????:?125?/1?? » 6?????:?85?×6?=?510? » 6?????:?125?×6=?750? ???WebLogic Server???????????????????????????????/?????????CPU??????(CPU????????)?8???CPU?2?(CPU???=16??)??????????????????????6?????????????? · WebLogic Server Standard Edition » ???????:?216?(?108?×2CPU) » ????:?48?/1??(?24?×2CPU) ?????????22% » 6?????:?216+?48?×6=?504? ????JBoss EAP Standard??Premium?WebLogic Server Standard Edition???????????????????? ???????JBoss EAP Premium???3?????Standard??6????????????? ???????????WebLogic Server Standard Edition?????????????????????JBoss EAP????CPU??????????WebLogic Server Standard Edition?CPU?????????????1CPU????????????????????WebLogic Server Standard Edition????????????? ?????WebLogic Server??Java???????????????????????????????????????JBoss EAP?????????????Java SE????????????????????????WebLogic Server???????? ????WebLogic Server???????????????????????????????????JBoss EAP???????????????????????????????????????WebLogic Server?????????????????????WebLogic Server??????????????·??????????????????? ???2012?9????Oracle Technolorgy Network???????????WebLogic Server???????????????????????????????????????????????????????? ????????????????????????????????JBoss EAP????TCO???????????????????????????????????WebLogic Server????????????????????????????WebLogic Server????????????????????????????????????????????

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  • GPU Debugging with VS 11

    - by Daniel Moth
    With VS 11 Developer Preview we have invested tremendously in parallel debugging for both CPU (managed and native) and GPU debugging. I'll be doing a whole bunch of blog posts on those topics, and in this post I just wanted to get people started with GPU debugging, i.e. with debugging C++ AMP code. First I invite you to watch 6 minutes of a glimpse of the C++ AMP debugging experience though this video (ffw to minute 51:54, up until minute 59:16). Don't read the rest of this post, just go watch that video, ideally download the High Quality WMV. Summary GPU debugging essentially means debugging the lambda that you pass to the parallel_for_each call (plus any functions you call from the lambda, of course). CPU debugging means debugging all the code above and below the parallel_for_each call, i.e. all the code except the restrict(direct3d) lambda and the functions that it calls. With VS 11 you have to choose what debugger you want to use for a particular debugging session, CPU or GPU. So you can place breakpoints all over your code, then choose what debugger you want (CPU or GPU), and you'll only be able to hit breakpoints for the code type that the debugger engine understands – the remaining breakpoints will appear as unbound. If you want to hit the unbound breakpoints, you'd have to stop debugging, and start again with the other debugger. Sorry. We suck. We know. But once you are past that limitation, I think you'll find the experience truly rewarding – seriously! Switching debugger engines With the Developer Preview bits, one way to switch the debugger engine is through the project properties – see the screenshots that follow. This one is showing the CPU option selected, which is basically the default that you are all familiar with: This screenshot is showing the GPU option selected, by changing the debugger launcher (notice that this applies for both the local and remote case): You actually do not have to open the project properties just for switching the debugger engine, you can switch the selection from the toolbar in VS 11 Developer Preview too – see following screenshot (the effect is the same as if you opened the project properties and switched there) Breakpoint behavior Here are two screenshots, one showing a debugging session for CPU and the other a debugging session for GPU (notice the unbound breakpoints in each case) …and here is the GPU case (where we cannot bind the CPU breakpoints but can the GPU breakpoint, which is actually hit) Give C++ AMP debugging a try So to debug your C++ AMP code, pull down the drop down under the 'play' button to select the 'GPU C++ Direct3D Compute Debugger' menu option, then hit F5 (or the 'play' button itself). Then you can explore debugging by exploring the menus under the Debug and under the Debug->Windows menus. One way to do that exploration is through the C++ AMP debugging walkthrough on MSDN. Another way to explore the C++ AMP debugging experience, you can use the moth.cpp code file, which is what I used in my BUILD session debugger demo. Note that for my demo I was using the latest internal VS11 bits, so your experience with the Developer Preview bits won't be identical to what you saw me demonstrate, but it shouldn't be far off. Stay tuned for a lot more content on the parallel debugger in VS 11, both CPU and GPU, both managed and native. Comments about this post by Daniel Moth welcome at the original blog.

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  • collectd does not work

    - by bery
    I have installed collectd-5.0.0 on Fedora12 server and would like to run its service for receiving data from clients. I have enabled network plugin and rddtool plugin as commented: collectd.conf in server: BaseDir "/opt/collectd/var/lib/collectd" LoadPlugin "logfile" LoadPlugin network LoadPlugin rrdtool <Plugin network> Listen "192.168.8.37" "25826" </Plugin> collectd.conf in client: LoadPlugin logfile LoadPlugin cpu LoadPlugin network LoadPlugin memory <Plugin network> Server"192.168.8.37" "25826" </Plugin> collectd.log in server: [2011-08-03 02:36:04] Exiting normally. [2011-08-03 02:36:04] rrdtool plugin: Shutting down the queue thread. [2011-08-03 02:36:04] network plugin: Stopping receive thread. [2011-08-03 02:36:04] network plugin: Stopping dispatch thread. [2011-08-03 02:37:11] Initialization complete, entering read-loop. collectd.log in client: [2011-08-02 17:31:44] Initialization complete, entering read-loop. results thst execute netstat on server: netstat -ulpn | grep 25826 udp 0 0 192.168.8.37:25826 0.0.0.0:* 4744/collectd problem: but there is noting in "/opt/collectd/var/lib/collectd/" on ser yes,I move the port number of "25826" as your propose(But I think this is the default port for coolectd).there is no rdd files recived on server. collectd.log in client collectd [2011-08-03 10:01:36] plugin_read_thread: Handling memory'. [2011-08-03 10:01:36] plugin_read_thread: Handlingcpu'. [2011-08-03 10:01:36] plugin_dispatch_values: time = 1312380096.431; interval = 10.000; host = uml; plugin = memory; plugin_instance = ; type = memory; type_instance = used; [2011-08-03 10:01:36] plugin_dispatch_values: time = 1312380096.431; interval = 10.000; host = uml; plugin = cpu; plugin_instance = 0; type = cpu; type_instance = user; [2011-08-03 10:01:36] uc_update: uml/memory/memory-used: ds[0] = 280412160.000000 [2011-08-03 10:01:36] plugin: plugin_write: Writing values via network. [2011-08-03 10:01:36] uc_update: uml/cpu-0/cpu-user: ds[0] = 0.100008 [2011-08-03 10:01:36] plugin: plugin_write: Writing values via network. [2011-08-03 10:01:36] plugin_dispatch_values: time = 1312380096.431; interval = 10.000; host = uml; plugin = memory; plugin_instance = ; type = memory; type_instance = buffered; [2011-08-03 10:01:36] plugin_dispatch_values: time = 1312380096.431; interval = 10.000; host = uml; plugin = cpu; plugin_instance = 0; type = cpu; type_instance = nice; [2011-08-03 10:01:36] uc_update: uml/memory/memory-buffered: ds[0] = 344182784.000000 [2011-08-03 10:01:36] plugin: plugin_write: Writing values via network. [2011-08-03 10:01:36] uc_update: uml/cpu-0/cpu-nice: ds[0] = 0.000000 [2011-08-03 10:01:36] plugin: plugin_write: Writing values via network. [2011-08-03 10:01:36] network plugin: flush_buffer: send_buffer_fill = 1340 [2011-08-03 10:01:36] network plugin: network_send_buffer: buffer_len = 1340 ... [2011-08-03 10:01:36] plugin_read_thread: Next read of the cpu plugin at 1312380106.429064774. collectd.log in server collectd: [2011-08-03 20:18:08] type = network [2011-08-03 20:18:08] type = rrdtool [2011-08-03 20:18:08] network plugin: sockent_open: node = 192.168.8.37; service = 25826; [2011-08-03 20:18:08] fd = 3; calling bind' [2011-08-03 20:18:08] Done parsing/opt/collectd//share/collectd/types.db' [2011-08-03 20:18:08] interval_g = 10; [2011-08-03 20:18:08] timeout_g = 2; [2011-08-03 20:18:08] hostname_g = localhost.localdomain; [2011-08-03 20:18:08] Initialization complete, entering read-loop. It looks like, data is sending but doesn't be recived. Where is the mistake?

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  • Installation problem Ubuntu 12.04 Crashing hardware error

    - by user93640
    I am running on Ubuntu 8.04 for quite some time without many problems. About almost a year ago or so I have been trying to upgrade to 10.04 LTS, but without any success. Each time when trying to upgrade or even newly install the installation process crashed after about an hour or so (I forgot exactly how long). Now I wanted to try Ubuntu 12.04 (not even installing, but I only selected "Try Ubuntu without installing") and I got similar errors. I did not try to install it, because of earlier experience with 10.04 when after I also lost 8.04 and had to install from scratch again (after which it worked). I get the following screen (as I am not allowed to upload photos here the text): 26.767262] [Hardware Error]: CPU 0: Machine Check Exception: 0 Bank 5: b200001804000e0f 26.767279] [Hardware Error]: TSC 0 26.767287] [Hardware Error]: PROCESSOR 0:6f6 TIME 1349017924 SOCKET 0 APIC 0 microcode 44 26.767297] [Hardware Error]: Run the above through 'mcelog --ascii' 26.767307] [Hardware Error]: CPU 1: Machine Check Exception: 0 Bank 1: b200000000000175 26.767316] [Hardware Error]: TSC 0 26.767323] [Hardware Error]: PROCESSOR 0:6f6 TIME 1349017924 SOCKET 0 APIC 1 microcode 44 26.767331] [Hardware Error]: Run the above through 'mcelog --ascii' 26.767339] [Hardware Error]: CPU 1: Machine Check Exception: 0 Bank 5: b200003000000e0f 26.767348] [Hardware Error]: TSC 0 26.767354] [Hardware Error]: PROCESSOR 0:6f6 TIME 1349017924 SOCKET 0 APIC 1 microcode 44 26.767363] [Hardware Error]: Run the above through 'mcelog --ascii' 26.767371] [Hardware Error]: CPU 1: Machine Check Exception: 4 Bank 1: b200000000000175 26.767379] [Hardware Error]: TSC 1bf231e65f 26.767386] [Hardware Error]: PROCESSOR 0:6f6 TIME 1349017951 SOCKET 0 APIC 1 microcode 44 26.767395] [Hardware Error]: Run the above through 'mcelog --ascii' 26.767403] [Hardware Error]: CPU 1: Machine Check Exception: 4 Bank 5: b200003008000e0f 26.767413] [Hardware Error]: TSC 1bf231e65f 26.767421] [Hardware Error]: PROCESSOR 0:6f6 TIME 1349017951 SOCKET 0 APIC 1 microcode 44 26.767429] [Hardware Error]: Run the above through 'mcelog --ascii' 26.767437] [Hardware Error]: CPU 0: Machine Check Exception: 5 Bank 5: b200001806000e0f 26.767447] [Hardware Error]: RIP |INEXACT| 60:<00000000c1018b5c> {mwait_idle+0x7c/0x1d0} 26.767464] [Hardware Error]: TSC 1bf231e674 26.767471] [Hardware Error]: PROCESSOR 0:6f6 TIME 1349017951 SOCKET 0 APIC 0 microcode 44 26.767480] [Hardware Error]: Run the above through 'mcelog --ascii' 26.767487] [Hardware Error]: Machine check: Processor context corrupt 26.767495] Kernel panic - not syncing: Fatal Machine check 26.767505] Pid: 579, comm: debconf-communi Tainted: G M 3.2.0.29-generic-pae #46-Ubuntu 26.767515] Call Trace: 26.767525] [<c158f812>] ? printk+0x2d/0x2f 26.767534] [<c158f6e0>] panic+0x5c/0x161 26.767542] [<c10247ef>] mce_panic.part.14+0x13f/0x170 26.767551] [<c1024872>] mce_panic+0x52/0x90 26.767558] [<c1024a18>] mce_reign+0x168/0x170 26.767565] [<c1024bb5>] mce_end+0x105/0x110 26.767572] [<c10252db>] do_machine_check+0x32b/0x4f0 26.767581] [<c1024fb0>] ? mce_log+0x120/0x120 26.767590] [<c15a5e47>] error_code+0x67/0x6c 26.767602] panic occurred, switching back to text console 26.768498] Rebooting in 30 seconds.. For information, I have also tried earlier Arch Linux. I can install it, but when I try to install a window manager (LXDE) again I got similar errors. Fedora also crashes when installing and also Mandriva did not work for me. Therefore I think something deep in the machine might be wrong. But as stated above I can (clean) install 8.04 and also 9.10 can be installed without problems. Also updates for 8.04 can be installed. My machine is dual boot with XP next to it on a different partition. My HW: Memory : 2.0 GiB; Processor 0: Intel(R) Core(TM)2 CPU 6320 @ 1.86GHz; Processor 1: Intel(R) Core(TM)2 CPU 6320 @ 1.86GHz; How can I install Ubuntu 12.04? Last option would be to completely format my machine and install everything from scratch, but even I am not sure if that would solve it in the end. Can anybody help me out?

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  • How to run Cg vertex/fragment shader on CPU?

    - by Andy
    Hi all, I'm playing about with some vertex and fragment shaders using Cg on my little netbook (running Linux). Clearly I'm going to frequently hit resource limits for my graphics controller, so was wondering if there's a nice way to run the shaders on the CPU, just to test them. Something like D3D's refrast... TIA Andy

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  • How do I get the CPU speed and total physical ram in C#?

    - by edude05
    I need a simple way of checking how much ram and fast the CPU of the host PC is. I tried WMI however the code I'm using private long getCPU() { ManagementClass mObject = new ManagementClass("Win32_Processor"); mObject.Get(); return (long)mObject.Properties["MaxClockSpeed"].Value; } Throws a null reference exception. Furthermore, WMI queries are a bit slow and I need to make a few to get all the specs. Is there a better way?

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  • What is a good CPU/PC setup to speed up intensive C++/templates compilation?

    - by ApplePieIsGood
    I currently have a machine with an Opteron 275 (2.2Ghz), which is a dual core CPU, and 4GB of RAM, along with a very fast hard drive. I find that when compiling even somewhat simple projects that use C++ templates (think boost, etc.), my compile times can take quite a while (minutes for small things, much longer for bigger projects). Unfortunately only one of the cores is pegged at 100%, so I know it's not the I/O, and it would seem that there is no way to take advantage of the other core for C++ compilation?

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  • Attempting to load a 64-bit application, how this CPU is not compatible with 64-bit mode

    - by Brandon Michael Hunter
    I have a Dell Studio 540, 64 bit OS Windows Home Premium. My CPU is supports Intel's virtualization technology, but I don't know how to enabled it on my machine. I saw that you can do it via the bios, but I didn't see this option when going through my BIOS. Is there another way to enabled this feature? Please let me know. I'm trying to installed Windows Server 2008 via Vircutal PC 2007. Thank You,

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  • Do really need a count lock on Multi threads with one CPU core?

    - by MrROY
    If i have some code looks like this(Please ignore the syntax, i want to understand it without a specified language): count = 0 def countDown(): count += 1 if __name__ == '__main__': thread1(countDown) thread2(countDown) thread3(countDown) Here i have a CPU with only one core, do i really need a lock to the variable count in case of it could be over-written by other threads. I don't know, but if the language cares a lot, please explain it under Java?C and Python, So many thanks.

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  • Is it possible to profile CPU / memory inside an Adobe AIR application?

    - by dain
    Couldn`t find any ActionScript native APIs even in the beta documentation, am I right supposing that this means the only way to measure CPU / memory consumption is by cooking up a custom native solution, hooking it up with AIR and making it work on each targeted platform? Basically the aim is to be able to have this information available inside AIR and not having to use an external application for profiling, not even Flex / Flash builder.

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  • S5000XVN Intel Motherboard - Only sees 12 out of 16GB of RAM

    - by Richie086
    So I have an older Intel S5000XVN motherboard, here are the specs CPU Arch : 2 CPU - 2 Cores - 2 Threads CPU PSN : Intel Xeon CPU 5160 @ 3.00GHz CPU EXT : MMX, SSE (1, 2, 3, 3S), EM64T, VT-x CPUID : 6.F.6 / Extended : 6.F CPU Cache : L1 : 2 x 32 / 2 x 32 KB - L2 : 4096 KB Core : Woodcrest (65 nm) / Stepping : B2 Freq : 2985.21 MHz (331.69 * 9) MB Brand : Intel MB Model : S5000XVN NB : Intel 5000X rev 31 SB : Intel 6321ESB rev 09 RAM : 16384 MB FB-DDR2 RAM Speed : 331.7 MHz (1:1) @ N/A Slot 1 : 2048MB (5300) Slot 1 Manufacturer : Kingston Slot 2 : 2048MB (5300) Slot 2 Manufacturer : Qimonda Slot 3 : 2048MB (5300) Slot 3 Manufacturer : Kingston Slot 4 : 2048MB (5300) Slot 4 Manufacturer : Qimonda Slot 5 : 2048MB (5300) Slot 5 Manufacturer : Kingston Slot 6 : 2048MB (5300) Slot 6 Manufacturer : Qimonda As you can clearly see, CPU-Z says I have 16GB of PC2-5300 RAM installed. For some reason in both BIOS and in Windows the maximum usable RAM is 12GB instead of 16GB. I have a dedicated video card connnected, so it can't be stealing RAM to use for the GPU (the S5000XVN does not have any onboard video). I am running Windows Server 2008 R2 x64 as the primary OS - so there should not be a memory limitation imposed on me from the OS. Has anyone experienced this before? Any ideas on how I can actually use all 16GB of RAM? I plan on using this machine to use for a Hyper-V server and have x2 Quad Core Xeon CPUs on the way as I write this post.

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  • Is this processor burned?

    - by Jhonnytunes
    I've recently exchange the processors in two PCChips boards. Both boards are LGA775. Board A is P17G(Pentium 4 HyperThreading 3GHz) and board B is P49G(Pentium Dual Core 3GHz). I use board A to watch videos, and some of them are 3GB size and this is why I exchanged the CPU. I installed Dual Core in board A and it worked out of the box, now 3GB videos use 5% of CPU instead of 50%. When I installed the pentium in the board B, I forgot to connect the 4pin power and, when i powered on the PC, the CPU fan stay off. Then, I connected all right this time, and now the board doesnt show video. I think the CPU is not working but im not sure about that. The PC turns on and the HD spins, the CPU fan spins, network socket blinking, but not video and case power led is neither blinking. I tried with other PSU and everything was the same. I figure out that CPU have that paste above. IDK really what's happening, I hope I dont have to buy another CPU. Is it Burned?

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  • .NET Code Evolution

    - by Alois Kraus
    Originally posted on: http://geekswithblogs.net/akraus1/archive/2013/07/24/153504.aspxAt my day job I do look at a lot of code written by other people. Most of the code is quite good and some is even a masterpiece. And there is also code which makes you think WTF… oh it was written by me. Hm not so bad after all. There are many excuses reasons for bad code. Most often it is time pressure followed by not enough ambition (who cares) or insufficient training. Normally I do care about code quality quite a lot which makes me a (perceived) slow worker who does write many tests and refines the code quite a lot because of the design deficiencies. Most of the deficiencies I do find by putting my design under stress while checking for invariants. It does also help a lot to step into the code with a debugger (sometimes also Windbg). I do this much more often when my tests are red. That way I do get a much better understanding what my code really does and not what I think it should be doing. This time I do want to show you how code can evolve over the years with different .NET Framework versions. Once there was  time where .NET 1.1 was new and many C++ programmers did switch over to get rid of not initialized pointers and memory leaks. There were also nice new data structures available such as the Hashtable which is fast lookup table with O(1) time complexity. All was good and much code was written since then. At 2005 a new version of the .NET Framework did arrive which did bring many new things like generics and new data structures. The “old” fashioned way of Hashtable were coming to an end and everyone used the new Dictionary<xx,xx> type instead which was type safe and faster because the object to type conversion (aka boxing) was no longer necessary. I think 95% of all Hashtables and dictionaries use string as key. Often it is convenient to ignore casing to make it easy to look up values which the user did enter. An often followed route is to convert the string to upper case before putting it into the Hashtable. Hashtable Table = new Hashtable(); void Add(string key, string value) { Table.Add(key.ToUpper(), value); } This is valid and working code but it has problems. First we can pass to the Hashtable a custom IEqualityComparer to do the string matching case insensitive. Second we can switch over to the now also old Dictionary type to become a little faster and we can keep the the original keys (not upper cased) in the dictionary. Dictionary<string, string> DictTable = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase); void AddDict(string key, string value) { DictTable.Add(key, value); } Many people do not user the other ctors of Dictionary because they do shy away from the overhead of writing their own comparer. They do not know that .NET has for strings already predefined comparers at hand which you can directly use. Today in the many core area we do use threads all over the place. Sometimes things break in subtle ways but most of the time it is sufficient to place a lock around the offender. Threading has become so mainstream that it may sound weird that in the year 2000 some guy got a huge incentive for the idea to reduce the time to process calibration data from 12 hours to 6 hours by using two threads on a dual core machine. Threading does make it easy to become faster at the expense of correctness. Correct and scalable multithreading can be arbitrarily hard to achieve depending on the problem you are trying to solve. Lets suppose we want to process millions of items with two threads and count the processed items processed by all threads. A typical beginners code might look like this: int Counter; void IJustLearnedToUseThreads() { var t1 = new Thread(ThreadWorkMethod); t1.Start(); var t2 = new Thread(ThreadWorkMethod); t2.Start(); t1.Join(); t2.Join(); if (Counter != 2 * Increments) throw new Exception("Hmm " + Counter + " != " + 2 * Increments); } const int Increments = 10 * 1000 * 1000; void ThreadWorkMethod() { for (int i = 0; i < Increments; i++) { Counter++; } } It does throw an exception with the message e.g. “Hmm 10.222.287 != 20.000.000” and does never finish. The code does fail because the assumption that Counter++ is an atomic operation is wrong. The ++ operator is just a shortcut for Counter = Counter + 1 This does involve reading the counter from a memory location into the CPU, incrementing value on the CPU and writing the new value back to the memory location. When we do look at the generated assembly code we will see only inc dword ptr [ecx+10h] which is only one instruction. Yes it is one instruction but it is not atomic. All modern CPUs have several layers of caches (L1,L2,L3) which try to hide the fact how slow actual main memory accesses are. Since cache is just another word for redundant copy it can happen that one CPU does read a value from main memory into the cache, modifies it and write it back to the main memory. The problem is that at least the L1 cache is not shared between CPUs so it can happen that one CPU does make changes to values which did change in meantime in the main memory. From the exception you can see we did increment the value 20 million times but half of the changes were lost because we did overwrite the already changed value from the other thread. This is a very common case and people do learn to protect their  data with proper locking.   void Intermediate() { var time = Stopwatch.StartNew(); Action acc = ThreadWorkMethod_Intermediate; var ar1 = acc.BeginInvoke(null, null); var ar2 = acc.BeginInvoke(null, null); ar1.AsyncWaitHandle.WaitOne(); ar2.AsyncWaitHandle.WaitOne(); if (Counter != 2 * Increments) throw new Exception(String.Format("Hmm {0:N0} != {1:N0}", Counter, 2 * Increments)); Console.WriteLine("Intermediate did take: {0:F1}s", time.Elapsed.TotalSeconds); } void ThreadWorkMethod_Intermediate() { for (int i = 0; i < Increments; i++) { lock (this) { Counter++; } } } This is better and does use the .NET Threadpool to get rid of manual thread management. It does give the expected result but it can result in deadlocks because you do lock on this. This is in general a bad idea since it can lead to deadlocks when other threads use your class instance as lock object. It is therefore recommended to create a private object as lock object to ensure that nobody else can lock your lock object. When you read more about threading you will read about lock free algorithms. They are nice and can improve performance quite a lot but you need to pay close attention to the CLR memory model. It does make quite weak guarantees in general but it can still work because your CPU architecture does give you more invariants than the CLR memory model. For a simple counter there is an easy lock free alternative present with the Interlocked class in .NET. As a general rule you should not try to write lock free algos since most likely you will fail to get it right on all CPU architectures. void Experienced() { var time = Stopwatch.StartNew(); Task t1 = Task.Factory.StartNew(ThreadWorkMethod_Experienced); Task t2 = Task.Factory.StartNew(ThreadWorkMethod_Experienced); t1.Wait(); t2.Wait(); if (Counter != 2 * Increments) throw new Exception(String.Format("Hmm {0:N0} != {1:N0}", Counter, 2 * Increments)); Console.WriteLine("Experienced did take: {0:F1}s", time.Elapsed.TotalSeconds); } void ThreadWorkMethod_Experienced() { for (int i = 0; i < Increments; i++) { Interlocked.Increment(ref Counter); } } Since time does move forward we do not use threads explicitly anymore but the much nicer Task abstraction which was introduced with .NET 4 at 2010. It is educational to look at the generated assembly code. The Interlocked.Increment method must be called which does wondrous things right? Lets see: lock inc dword ptr [eax] The first thing to note that there is no method call at all. Why? Because the JIT compiler does know very well about CPU intrinsic functions. Atomic operations which do lock the memory bus to prevent other processors to read stale values are such things. Second: This is the same increment call prefixed with a lock instruction. The only reason for the existence of the Interlocked class is that the JIT compiler can compile it to the matching CPU intrinsic functions which can not only increment by one but can also do an add, exchange and a combined compare and exchange operation. But be warned that the correct usage of its methods can be tricky. If you try to be clever and look a the generated IL code and try to reason about its efficiency you will fail. Only the generated machine code counts. Is this the best code we can write? Perhaps. It is nice and clean. But can we make it any faster? Lets see how good we are doing currently. Level Time in s IJustLearnedToUseThreads Flawed Code Intermediate 1,5 (lock) Experienced 0,3 (Interlocked.Increment) Master 0,1 (1,0 for int[2]) That lock free thing is really a nice thing. But if you read more about CPU cache, cache coherency, false sharing you can do even better. int[] Counters = new int[12]; // Cache line size is 64 bytes on my machine with an 8 way associative cache try for yourself e.g. 64 on more modern CPUs void Master() { var time = Stopwatch.StartNew(); Task t1 = Task.Factory.StartNew(ThreadWorkMethod_Master, 0); Task t2 = Task.Factory.StartNew(ThreadWorkMethod_Master, Counters.Length - 1); t1.Wait(); t2.Wait(); Counter = Counters[0] + Counters[Counters.Length - 1]; if (Counter != 2 * Increments) throw new Exception(String.Format("Hmm {0:N0} != {1:N0}", Counter, 2 * Increments)); Console.WriteLine("Master did take: {0:F1}s", time.Elapsed.TotalSeconds); } void ThreadWorkMethod_Master(object number) { int index = (int) number; for (int i = 0; i < Increments; i++) { Counters[index]++; } } The key insight here is to use for each core its own value. But if you simply use simply an integer array of two items, one for each core and add the items at the end you will be much slower than the lock free version (factor 3). Each CPU core has its own cache line size which is something in the range of 16-256 bytes. When you do access a value from one location the CPU does not only fetch one value from main memory but a complete cache line (e.g. 16 bytes). This means that you do not pay for the next 15 bytes when you access them. This can lead to dramatic performance improvements and non obvious code which is faster although it does have many more memory reads than another algorithm. So what have we done here? We have started with correct code but it was lacking knowledge how to use the .NET Base Class Libraries optimally. Then we did try to get fancy and used threads for the first time and failed. Our next try was better but it still had non obvious issues (lock object exposed to the outside). Knowledge has increased further and we have found a lock free version of our counter which is a nice and clean way which is a perfectly valid solution. The last example is only here to show you how you can get most out of threading by paying close attention to your used data structures and CPU cache coherency. Although we are working in a virtual execution environment in a high level language with automatic memory management it does pay off to know the details down to the assembly level. Only if you continue to learn and to dig deeper you can come up with solutions no one else was even considering. I have studied particle physics which does help at the digging deeper part. Have you ever tried to solve Quantum Chromodynamics equations? Compared to that the rest must be easy ;-). Although I am no longer working in the Science field I take pride in discovering non obvious things. This can be a very hard to find bug or a new way to restructure data to make something 10 times faster. Now I need to get some sleep ….

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