[lkml]   [2003]   [Feb]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    Subject[PATCH] (0-2) governors for 60-bk

    Here is an update of my thread group and user governor patch. This
    patch reduces timeslices of process belonging to groups with too many
    active processes. This, in effect, lowers their priority and makes
    it more likely that other tasks can run preventing tasks in a governed
    group from using too large a share of the the cpu.

    There is a governor for thread groups, which are defined as processes
    sharing both mm and files or processes with CLONE_THREAD set. The
    default governor is set to 1.5 threads (15). This means that when
    there are 2 or more threads active the timeslices will be reduced
    as follows:

    slice = (slice * 1.5) / 2

    A second governor is defined for user processes. This one defaults
    to 30 active task (300). A process has only one governor. If its
    a member of a thread group that governor applies and it is ignored
    by the user governor process.

    A couple of notes about the patch. There is debug code in
    sched.c that can be enabled if you want to see what is happening.
    I would not recommend this code be used on NUMA systems. I am
    looking into a version of the patch that would impose the governors
    on a per node basis. Earlier versions of this patch counted user
    processes incorrectly which caused the user governor to trigger
    limiting users when it should not have. This is now fixed.

    As it stands now a modified schedule-tunables patch based off the one
    found in the mm kernels can optionally be applied. I think that using
    the rlimit infrastructure probably makes more sense - comments?

    The patches should apply to 60-mk and probably to -mm1 after reversing
    the schedule-tunables included in it.

    The patch as been tested on UP.

    As always comments/suggestion appriecated

    Ed Tomlinson

    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    More majordomo info at
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:33    [W:0.020 / U:7.660 seconds]
    ©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site