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Subject: Re: RFC: documentation of the autogroup feature
To: Mike Galbraith <efault@gmx.de>
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From: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
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Date: Sun, 27 Nov 2016 22:13:26 +0100
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Hi Mike,

On 11/23/2016 04:33 PM, Mike Galbraith wrote:
> On Wed, 2016-11-23 at 14:54 +0100, Michael Kerrisk (man-pages) wrote:
>> Hi Mike,

[...]

>> Actually, can you define for me what the root task group is, and 
>> why it exists? That may be worth some words in this man page.
> 
> I don't think we need group scheduling details, there's plenty of
> documentation elsewhere for those who want theory.  Autogroup is for
> those who don't want to have to care (which is also why it should have
> never grown nice knob).

Actually, the more I think about this, the more I think we *do*
need a few details on group scheduling. Otherwise, it's difficult
to explain to the use why nice(1) no longer works as traditionally
expected.

Here's my attempt to define the root task group:

       *  If autogrouping is disabled, then all processes in the root CPU
          cgroup form a scheduling group (sometimes called the "root task
          group").

Can you improve on this?

Cheers,

Michael

-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/