lkml.org 
[lkml]   [2009]   [Oct]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: sched regression introduced by NO_NEW_FAIR_SLEEPERS

    * drago01 <drago01@gmail.com> wrote:

    > On Sat, Oct 3, 2009 at 12:47 PM, Ingo Molnar <mingo@elte.hu> wrote:
    > >
    > > * drago01 <drago01@gmail.com> wrote:
    > >
    > >> On Sun, Sep 27, 2009 at 9:47 PM, drago01 <drago01@gmail.com> wrote:
    > >> > Hi,
    > >> >
    > >> > Chuck has backported some scheduler patches from 2.6.32 to the fedora kernel.
    > >> >
    > >> > I did the following test to test the new scheduler (cpu is a core i7
    > >> > 920 4 cores + HT).
    > >> >
    > >> > run 8 "md5sum /dev/urandom" task and try to use the desktop (compiz).
    > >> >
    > >> > The result was that moving windows or rotating the cube is very slow.
    > >> > (same happens with pure metacity but is is worse in compiz).
    > >> >
    > >> > Mounting debugfs and doing "echo NEW_FAIR_SLEEPERS > sched_features"
    > >> > results into a useable desktop while the 8 md5sum tasks are running
    > >> > (ie. the system behaves as if they where not running at all from an
    > >> > interactivity pov).
    > >> >
    > >> >
    > >> > P.S: please CC me when replying.
    > >> >
    > >>
    > >> With "NEW_FAIR_SLEEPERS" I can even run 100(!)  "md5sum" task without
    > >> any effect on interactivity. (still have not found a number of tasks
    > >> needed to make the system unresponsive as with 8 with
    > >> "NO_NEW_FAIR_SLEEPERS".
    > >
    > > Can you try the latest -tip tree please:
    > >
    > >  http://people.redhat.com/mingo/tip.git/README
    > >
    > > There we default to FAIR_SLEEPERS + GENTLE_FAIR_SLEEPERS - which should
    > > give much of the new-fair-sleepers advantage.
    >
    > OK, with this kernel it works fine (can spam the system with md5sum
    > tasks and the desktop is still responsive).
    >
    > Was able to use the system with 129 "md5sum /dev/urandom" running.

    ok, great!

    Those changes are in Linus's latest tree as well.

    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: 2009-10-03 16:55    [W:0.025 / U:0.196 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site