   Help: Slow system with 0 CPU usage
  EDIT: newcomers be sure to read my later posts - I have determined more detail.OK, simple problem - my system (or at least some applications) are being particularly unresponsive and sluggish, even with CPU completely unutilised (99-100% to the idle process). Windows XP x64, btw.In particular, Explorer and Tortise SVN (a shell extension) are particularly slow, so my guess something is wrong in the shell. Explorer takes half a second to register mouse-operations and such. Tortise SVN takes easily a second or two to respond to typing and other operations. GUI operations and redrawing also seem to be somewhat slow when task-swapping between applications.I've got several Office 2007 programs (OneNote, Word, Excel) open, Winamp, Process Explorer, an old version Acrobat Reader (5.1), Avast virus scanner, Google Desktop. I've opened and closed Acrobat Reader easily 100 times since my last reboot - so that might be it. It's also the first time I've used TSVN on Office documents, so that might also be it.Is there any way to "debug" this sort of problem? Normally if my system is slow I just pull up Process Explorer and look for what is eating CPU. But that's not helping in this case. Are there any other diagnostics I could use?This is probably the second or third time it has happened (and I've been doing the same activities with approximately the same programs each time), however it's quite a niggling, long-term problem, so solving it by experimental elimination probably isn't feasible.[Edited by - Andrew Russell on September 6, 2007 5:37:54 AM]
  Have you checked to see if your hard drives are set to DMA mode instead of PIO/LBA?If I remember correctly, some versions of Windows XP had the hard drives set to the slowest setting by default.   ;  I'm not really sure I've checked this properly. But it "seems fine". Certainly I've never had this sort of problem before, so I suspect the configuration should be ok.   ;  Interesting information:All my x64 applications seem to be running slow. 64-bit notepad.exe has the same suggish typing of TSVN. Even Process Explorer slows down when I change its priority to 8 (from 13). 32-bit processes seem unaffected.   ;  Windows will drop down to slower access modes if it encounters a certain number of access problems with the drive, though this should only really apply to optical drives.I've had issues with Tortoise SVN in the past, but it's been easy to spot as TSVNCache.exe was constantly hogging > 90% CPU time.I'd personally try disabling Google desktop, and see if that helps (Dell preinstalled it on the three Vista machines I've set up recently, and it performed very badly - though whether this is the fault of Vista's own indexing service, Dell's configuration or the software itself I couldn't tell you). On a related note, Foxit is a light, free PDF viewer.   ;  I think I've narrowed down the problem further. It stops happening when I close Word and comes back again when I run it again.Other than these couple of recent times, I can't say I've ever experienced this before - then again I'm not sure I've used Word alongside x64 applications much before.Of course, "don't use Word" isn't really a feasible solution for me. Any ideas now on identifying the problem and fixing it?Interestingly enough, Excel and OneNote have no effect.   ;  It sounds to me like you have some kind of disk access issue. As the Windows disk scheduler still really sucks hard, this is probably the case.Check your virtual memory settings (I've had XP flip them on me before when I started running out of disk space), check to make sure the disk is set to use DMA, and run a scandisk to make sure the filesystem is intact.One way to test this is to try opening the tray on the optical drive while the machine is running; if the machine suddenly speeds up you've got some sort of harddrive or optical drive access issue.As an aside, you can also get out of a lot of disk-related freezes in XP by generating an interrupt through the optical drive's eject button.If I knew more about x64 I could probably provide more advice. Does the problem go away when you reboot and run Word again?Also, IIRC Task Manager and Process Explorer don't show CPU usage taken up by external DLL invocation; it's possible Word is going out to some plugin or another that doesn't like your computer.   ;Quote:Original post by MithrandirHave you checked to see if your hard drives are set to DMA mode instead of PIO/LBA?If I remember correctly, some versions of Windows XP had the hard drives set to the slowest setting by default.where is this setting?   ;Quote:Original post by _SigmaQuote:Original post by MithrandirHave you checked to see if your hard drives are set to DMA mode instead of PIO/LBA?If I remember correctly, some versions of Windows XP had the hard drives set to the slowest setting by default.where is this setting?IIRC, it's under Device Manager, IDE Controllers, your IDE controller.   ;  "In particular, Explorer and Tortise SVN (a shell extension)"TortoiseSVN explains your problem. I find my work machine runs very slow, but I'm dealing with quite large repos's at work.   