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Subject: Re: [PATCH 1/9] Remove parent field in cpuacct cgroup
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Glauber Costa <glommer@parallels.com>
Cc: linux-kernel@vger.kernel.org, xemul@parallels.com, paul@paulmenage.org,
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Date: Mon, 19 Sep 2011 20:35:43 +0200
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On Mon, 2011-09-19 at 13:30 -0300, Glauber Costa wrote:
> For cpuusage, I am not sure this optimization is a valid one 

I was talking about cpuusage, cpuacct_charge() is called for every
ctxsw/tick.

But even for cpuacct tick stuff, wouldn't you need to sum all your child
cgroups to update the current cgroup? and that up the whole tree?