From: Mike Galbraith <efault@gmx.de>
To: mtk.manpages@gmail.com
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
Ingo Molnar <mingo@kernel.org>,
linux-man <linux-man@vger.kernel.org>,
lkml <linux-kernel@vger.kernel.org>,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: RFC: documentation of the autogroup feature
Date: Tue, 29 Nov 2016 14:46:15 +0100 [thread overview]
Message-ID: <1480427175.10353.77.camel@gmx.de> (raw)
In-Reply-To: <CAKgNAkiLafr7KJNAo+_kwKQB7ueO-oontNL_FQrGtqitmJpEDg@mail.gmail.com>
On Tue, 2016-11-29 at 10:10 +0100, Michael Kerrisk (man-pages) wrote:
> Let's try and go further. How's this:
>
> When scheduling non-real-time processes (i.e., those scheduled
> under the SCHED_OTHER, SCHED_BATCH, and SCHED_IDLE policies), the
> CFS scheduler employs a technique known as "group scheduling", if
> the kernel was configured with the CONFIG_FAIR_GROUP_SCHED option
> (which is typical).
>
> Under group scheduling, threads are scheduled in "task groups".
> Task groups have a hierarchical relationship, rooted under the
> initial task group on the system, known as the "root task group".
> Task groups are formed in the following circumstances:
>
> * All of the threads in a CPU cgroup form a task group. The par‐
> ent of this task group is the task group of the corresponding
> parent cgroup.
>
> * If autogrouping is enabled, then all of the threads that are
> (implicitly) placed in an autogroup (i.e., the same session, as
> created by setsid(2)) form a task group. Each new autogroup is
> thus a separate task group. The root task group is the parent
> of all such autogroups.
>
> * If autogrouping is enabled, then the root task group consists
> of all processes in the root CPU cgroup that were not otherwise
> implicitly placed into a new autogroup.
>
> * If autogrouping is disabled, then the root task group consists
> of all processes in the root CPU cgroup.
>
> * If group scheduling was disabled (i.e., the kernel was config‐
> ured without CONFIG_FAIR_GROUP_SCHED), then all of the pro‐
> cesses on the system are notionally placed in a single task
> group.
Notionally works for me.
-Mike
prev parent reply other threads:[~2016-11-29 13:48 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-22 15:59 RFC: documentation of the autogroup feature Michael Kerrisk (man-pages)
2016-11-23 10:33 ` [patch] sched/autogroup: Fix 64bit kernel nice adjustment Mike Galbraith
2016-11-23 13:47 ` Michael Kerrisk (man-pages)
2016-11-23 14:12 ` Mike Galbraith
2016-11-23 14:20 ` Michael Kerrisk (man-pages)
2016-11-23 15:55 ` Mike Galbraith
2016-11-24 6:24 ` [tip:sched/urgent] sched/autogroup: Fix 64-bit kernel nice level adjustment tip-bot for Mike Galbraith
2016-11-23 11:39 ` RFC: documentation of the autogroup feature Mike Galbraith
2016-11-23 13:54 ` Michael Kerrisk (man-pages)
2016-11-23 15:33 ` Mike Galbraith
2016-11-23 16:04 ` Michael Kerrisk (man-pages)
2016-11-23 17:11 ` Mike Galbraith
2016-11-24 21:41 ` RFC: documentation of the autogroup feature [v2] Michael Kerrisk (man-pages)
2016-11-25 12:52 ` Afzal Mohammed
2016-11-25 13:04 ` Michael Kerrisk (man-pages)
2016-11-25 13:02 ` Mike Galbraith
2016-11-25 15:04 ` Michael Kerrisk (man-pages)
2016-11-25 15:48 ` Michael Kerrisk (man-pages)
2016-11-25 15:51 ` Mike Galbraith
2016-11-25 16:08 ` Michael Kerrisk (man-pages)
2016-11-25 16:18 ` Peter Zijlstra
2016-11-25 16:34 ` Michael Kerrisk (man-pages)
2016-11-25 20:54 ` Michael Kerrisk (man-pages)
2016-11-25 21:49 ` Peter Zijlstra
2016-11-29 7:43 ` Michael Kerrisk (man-pages)
2016-11-29 11:46 ` Peter Zijlstra
2016-11-29 13:44 ` Michael Kerrisk (man-pages)
2016-11-25 16:04 ` Peter Zijlstra
2016-11-25 16:13 ` Peter Zijlstra
2016-11-25 16:33 ` Michael Kerrisk (man-pages)
2016-11-25 22:48 ` Peter Zijlstra
2016-11-23 16:05 ` RFC: documentation of the autogroup feature Michael Kerrisk (man-pages)
2016-11-23 17:19 ` Mike Galbraith
2016-11-23 22:12 ` Michael Kerrisk (man-pages)
2016-11-27 21:13 ` Michael Kerrisk (man-pages)
2016-11-28 1:46 ` Mike Galbraith
[not found] ` <1127218a-dd9b-71a8-845d-3a83969632fc@gmail.com>
2016-11-29 9:10 ` Michael Kerrisk (man-pages)
2016-11-29 13:46 ` Mike Galbraith [this message]
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