lkml.org 
[lkml]   [2007]   [May]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: bad networking related lag in v2.6.22-rc2

    * Anant Nitya <kernel@prachanda.info> wrote:

    > Please ignore my last report about lag problem while using CFS-v13, it
    > is working perfectly fine with 2.6.21.1 and the lag I used to see in
    > v12 is not there with v13 anymore. After digging in a bit I found that
    > problem is only occurring in 2.6.22-rc1 and it get fired by network
    > usage while transmitting data upstream. I don't have any evidence that
    > CFS is involved in lag problem since 2.6.22-rc1 with stock scheduler
    > is also having same lag problem and it seems directly proportional
    > with upstream speed while downstream doesn't shows any misbehavior {
    > at lower upstream speed lag is less but with higher upstream speed
    > system starts crawling and system load hitting to 70/75}. Lets see how
    > 2.6.22-rc2 is doing.

    ok, i got your -rc2 debug numbers (off-list), and it doesnt look pretty:

    before-lag:

    sleep_max : 259502076
    block_max : 27690921
    wait_max : 16381558

    after-lag:

    sleep_max : 584186160
    block_max : 261780071
    wait_max : 881255577

    ouch! a nearly 1 second delay got observed by the scheduler - something
    is really killing your system!

    what does 'top' show during an upload? Is any system related task out of
    whack? Could you try to get a readprofile or an oprofile output from the
    kernel, so that we can see what is slowing it down so much? It could be
    something networking related in v2.6.22-rc2.

    Ingo
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2007-05-21 10:01    [W:0.023 / U:29.460 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site