lkml.org 
[lkml]   [2010]   [Nov]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH v4] sched: automated per session task groups
    From
    Date
    On Tue, 2010-11-30 at 14:18 +0100, Mike Galbraith wrote:
    >
    > From: Mike Galbraith <efault@gmx.de>
    > Date: Tue Nov 30 14:07:12 CET 2010
    > Subject: [PATCH] sched: Improve desktop interactivity: Implement automated per session task groups
    >
    > A recurring complaint from CFS users is that parallel kbuild has a negative
    > impact on desktop interactivity. This patch implements an idea from Linus,
    > to automatically create task groups. Currently, only per session autogroups
    > are implemented, but the patch leaves the way open for enhancement.
    >
    > Implementation: each task's signal struct contains an inherited pointer to
    > a refcounted autogroup struct containing a task group pointer, the default
    > for all tasks pointing to the init_task_group. When a task calls setsid(),
    > a new task group is created, the process is moved into the new task group,
    > and a reference to the preveious task group is dropped. Child processes
    > inherit this task group thereafter, and increase it's refcount. When the
    > last thread of a process exits, the process's reference is dropped, such
    > that when the last process referencing an autogroup exits, the autogroup
    > is destroyed.
    >
    > At runqueue selection time, IFF a task has no cgroup assignment, its current
    > autogroup is used.
    >
    > Autogroup bandwidth is controllable via setting it's nice level through the
    > proc filesystem. cat /proc/<pid>/autogroup displays the task's group and the
    > group's nice level. echo <nice level> > /proc/<pid>/autogroup Sets the task
    > group's shares to the weight of nice <level> task. Setting nice level is rate
    > limited for !admin users due to the abuse risk of task group locking.
    >
    > The feature is enabled from boot by default if CONFIG_SCHED_AUTOGROUP=y is
    > selected, but can be disabled via the boot option noautogroup, and can also
    > be turned on/off on the fly via..
    > echo [01] > /proc/sys/kernel/sched_autogroup_enabled.
    > ..which will automatically move tasks to/from the root task group.
    >
    > Signed-off-by: Mike Galbraith <efault@gmx.de>
    > Cc: Oleg Nesterov <oleg@redhat.com>
    > Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
    > Cc: Linus Torvalds <torvalds@linux-foundation.org>
    > Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
    > Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
    > LKML-Reference: <1290281700.28711.9.camel@maggy.simson.net>
    > Signed-off-by: Ingo Molnar <mingo@elte.hu>

    Looks good to me, Thanks Mike!

    Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>


    \
     
     \ /
      Last update: 2010-11-30 14:51    [W:0.029 / U:59.724 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site