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High DPC latency spikes RRS feed

  • 質問

  • I have Windows 7 pro 64 bit running on Intel core i5 @ Asus P8Z77-V and Creative Sound Blaster Z sound card. Recently (maybe about a couple of months) I began to hear certain sound clicks (not very frequent, but maybe one in a minute-two-three), so I begain to investigate the Internet and found the DPC issue threads. I've checked my system with DPC latency checker and found that sometimes there are unsystematical DPC latency spikes over 2ms:

    So, I did the xperf test at the time when DPC latency checker shows those spikes and found that no DPC runs longer than 256 usec!

    Total = 155031
    Elapsed Time, >        0 usecs AND <=        1 usecs,  84165, or  54.29%
    Elapsed Time, >        1 usecs AND <=        2 usecs,  26916, or  17.36%
    Elapsed Time, >        2 usecs AND <=        4 usecs,  13711, or   8.84%
    Elapsed Time, >        4 usecs AND <=        8 usecs,   7074, or   4.56%
    Elapsed Time, >        8 usecs AND <=       16 usecs,  10597, or   6.84%
    Elapsed Time, >       16 usecs AND <=       32 usecs,  10297, or   6.64%
    Elapsed Time, >       32 usecs AND <=       64 usecs,   1902, or   1.23%
    Elapsed Time, >       64 usecs AND <=      128 usecs,    348, or   0.22%
    Elapsed Time, >      128 usecs AND <=      256 usecs,     21, or   0.01%
    Total,                                                155031

    So, what could it be? ISR themselves? Or something running at even higher IRQL? Is there a way how to test it?

    The strange thing is that after I reboot my PC the systems maintains quite low DPC latency (< 500 us) for some time (maybe a few hours) and then these spikes begin to grow. Also I found that if I disable and re-enable my Intel network card (on the MB), the DPC latency spikes go away for some time (10-30 minutes) and then return back. I have installed the latest available driver for the Intel network adapter yesterday, but it doesn't solve the issue. Also I have all offloading options checked.

    Please, advice.


    • 編集済み Dmitriy_K 2014年1月12日 10:49
    2014年1月12日 10:43

回答

  • I would suggest you to check with the software vendor for more details on this.

    Arnav Sharma | Facebook | Twitter Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

    2014年1月12日 11:34
    モデレータ
  • Not intel, but http://www.thesycon.de/deu/latency_check.shtml

    Arnav Sharma | Facebook | Twitter Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

    2014年1月12日 17:10
    モデレータ
  • Thank you for (not)answering.

    I did a lot of research during the past days and found the following - no other device changes DPC latency except the network card build into my MB. If I disable and re-enable it or even change one of its parameters, the DPC latency goes back to normal for some time and then grows back to 2-4ms (maybe even more, I just didn't wait longer). So, I've checked network items that were associated with my network connection and found two additional NDIS drivers - Epfw lightweigh filter and Winpk lightweight filter.
    The first one is from Eset Smart security which I've installed myself and am using all the time. But I had quite old version - 5, so I decided to upgrade to the latest available (7). I am not sure whether such an upgrade really updates the NDIS driver but I've upgraded anyway.
    The source of the second one was a mystery to me, so I decided to remove it at all. And after a couple dozen minutes I understood who did install it - the ASUS Motherboard Utilities, which then stopped worked and completely died. OK, not a big loss since I almost don't use them. And.. magically DPC latency returned back to normal values. I am not sure what in particular caused the issue, but here is what I've done:
    1. Upgraded ESET Smart Security to version 7.
    2. Removed (uninstalled) winpk filter (not just unchecked it in the list, but did remove it).
    3. Quit ASUS Suite II (being honest it died itself for some reason).

    Though the latter research have shown that ASUS Suite II can cause occasional DPC spikes itself. Probably it accesses some motherboard-related drivers to get some info.
    • 回答としてマーク Dmitriy_K 2014年1月21日 2:14
    2014年1月21日 2:14

すべての返信

  • I would suggest you to check with the software vendor for more details on this.

    Arnav Sharma | Facebook | Twitter Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

    2014年1月12日 11:34
    モデレータ
  • You mean Intel?

    First I'd like to get to know what delays the DPCs if it is not processing of other DPCs. I'm not very familiar with performance analysis tools like xperf so I hope somebody here could help me with it.

    I saw some similar threads (but with Windows 8) here and the specialists analyzed *.etl files and pointed out which function took that much time. Unfortunately I can't do this myself.
    • 編集済み Dmitriy_K 2014年1月12日 11:46
    2014年1月12日 11:41
  • Not intel, but http://www.thesycon.de/deu/latency_check.shtml

    Arnav Sharma | Facebook | Twitter Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

    2014年1月12日 17:10
    モデレータ
  • Thank you for (not)answering.

    I did a lot of research during the past days and found the following - no other device changes DPC latency except the network card build into my MB. If I disable and re-enable it or even change one of its parameters, the DPC latency goes back to normal for some time and then grows back to 2-4ms (maybe even more, I just didn't wait longer). So, I've checked network items that were associated with my network connection and found two additional NDIS drivers - Epfw lightweigh filter and Winpk lightweight filter.
    The first one is from Eset Smart security which I've installed myself and am using all the time. But I had quite old version - 5, so I decided to upgrade to the latest available (7). I am not sure whether such an upgrade really updates the NDIS driver but I've upgraded anyway.
    The source of the second one was a mystery to me, so I decided to remove it at all. And after a couple dozen minutes I understood who did install it - the ASUS Motherboard Utilities, which then stopped worked and completely died. OK, not a big loss since I almost don't use them. And.. magically DPC latency returned back to normal values. I am not sure what in particular caused the issue, but here is what I've done:
    1. Upgraded ESET Smart Security to version 7.
    2. Removed (uninstalled) winpk filter (not just unchecked it in the list, but did remove it).
    3. Quit ASUS Suite II (being honest it died itself for some reason).

    Though the latter research have shown that ASUS Suite II can cause occasional DPC spikes itself. Probably it accesses some motherboard-related drivers to get some info.
    • 回答としてマーク Dmitriy_K 2014年1月21日 2:14
    2014年1月21日 2:14
  • i had a similar problem with my dell inspiron i5. this seemed to fix it 

    http://blogs.msdn.com/b/richin/archive/2010/11/26/how-to-disable-teredo-tunneling-pseudo-interface-6to4-adapter.aspx

    2016年3月6日 20:55