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Date: Fri, 19 Nov 2010 15:14:13 +0200
From: Andriy Gapon <avg@freebsd.org>
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To: Julian Elischer <julian@freebsd.org>
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Cc: Lucius Windschuh <lwindschuh@googlemail.com>,
	freebsd-performance@freebsd.org,
	FreeBSD Current <freebsd-current@freebsd.org>,
	FreeBSD Stable <freebsd-stable@freebsd.org>
Subject: Re: TTY task group scheduling
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on 18/11/2010 22:20 Julian Elischer said the following:
> tty grouping is a variant of what we used to have at one stage which is
> a "kernel schedulable entity group".. KSEG

Or rather, I think, a concrete application of a variant of that.

> the idea is that all items in a group share some characteristic and some amount
> of resources.
> 
> We stripped the KSEG out of the picture because it really complicated the picture.

Yes, unfortunately.
One can think about a number of applications for hierarchical schedulable
resources.  Even one-level group scheduling could be a very useful subcase.

BTW, http://www.mjmwired.net/kernel/Documentation/cgroups.txt
-- 
Andriy Gapon