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Subject: Re: [patch 00/18] CFS Bandwidth Control v7.2
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Vladimir Davydov <VDavydov@parallels.com>
Cc: Paul Turner <pjt@google.com>,
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        Ingo Molnar <mingo@elte.hu>, Pavel Emelianov <xemul@parallels.com>,
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Date: Mon, 19 Sep 2011 10:33:04 +0200
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On Mon, 2011-09-19 at 12:22 +0400, Vladimir Davydov wrote:
> But communicating tasks do not necessarily wake each other even if
> they exchange data through the pipe. And of course, if they use shared
> memory (e.g. threads), it is not obligatory at all. Also, the
> wake-affine path is cpu-load aware, i.e. it tries not to overload a
> cpu it is going to wake a task on. For instance, if we run a context
> switch test on an idle host, the two tasks will be executing on
> different cpus although it is better to execute them together on the
> same cpu.

This is not a problem specific to cgroups, and thus the solution
shouldn't ever live as something related to cgroups.