Need DPC (Deffered Procedure Call) experts!

Discussion in 'other software & services' started by funkydude, Dec 11, 2008.

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  1. funkydude

    funkydude Registered Member

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    Hello, I have little to no experience when it comes to DPC, but I've been having this problem with my laptop this month which seems to have arrive "out of the blue".

    I noticed it this week when I got completely random FPS drops whilst playing Left4Dead, so I looked at the Task Manager and realized that every short fps drop correlated with l4d's cpu usage dropping for a 1-2sec, but nothing was using that.

    I booted up Process Explorer from sysinternals and found out that every drop correlated with DPC using a large amount of cpu then dorpping back to 0.

    To sum it up it seems that because L4D uses nearly 100% cpu on both cores, it gets a stutter when DPC "steals" from it.

    I did research on DPC and used the Windows Performance Analyzer tools (xperf) to log what's using and here are the results:

    After playing L4D for a little bit to log these incidents, here's the table for DPC Usage:
    table.jpg

    ...and the graph:
    graph.jpg

    I can upload the log if needed. Was made with a xperf.exe -on DiagEasy


    I thought maybe there is a problem with some USB appliances so I unplugged them all and that usage went away, but I still got stutters ingame. Any ideas/opinions?
     
  2. funkydude

    funkydude Registered Member

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    Is this in the wrong forum?
     
  3. funkydude

    funkydude Registered Member

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    No one around with DPC experience?
     
  4. funkydude

    funkydude Registered Member

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    Just closing the issue, there appears to be a problem with my fan, at least, my CPU is overheating when playing a game. Since it is a laptop, it auto clocks down when it gets too hot, reaching 90C. The action of auto clocking down/up every 3 seconds or so because of the changing temperature was my main problem.
     
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