lkml.org 
[lkml]   [2004]   [Jul]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    Subject[patch] voluntary-preempt-2.6.8-rc2-I4

    * Ingo Molnar <mingo@elte.hu> wrote:

    > > > http://redhat.com/~mingo/voluntary-preempt/voluntary-preempt-2.6.8-rc2-I3
    > > >
    > > > it mainly fixes an ext3 livelock that could result in long delays during
    > > > heavy commit traffic.
    > >
    > > Hello Ingo, do you have any measurement of the improvement available ?
    >
    > it's a bug in the patch, not really a latency fix. When this (rare)
    > condition under heavy write traffic occurs then kjournald would loop for
    > many seconds (or tens of seconds) in __journal_clean_checkpoint_list(),
    > effectively hanging the system. The system is still preemptible but the
    > user cannot do much with it. Note that this condition is not present in
    > the vanilla kernel, it got introduced by earlier versions of
    > voluntary-preempt.

    there's one more new version:

    http://redhat.com/~mingo/voluntary-preempt/voluntary-preempt-2.6.8-rc2-I4

    this fixes another rare bug: release_task() could trigger a 'Badness'
    atomicity message when the right conditions occur on a preemptible
    kernel. This bugfix also allowed the addition of might_sleep() checks
    (and hence voluntary-preemption points) to dput() and fput(), two common
    functions.

    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: 2005-03-22 14:04    [W:3.119 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site