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Message-ID: <1332866823.16159.246.camel@twins>
Subject: Re: [PATCH 08/32] nohz: Try not to give the timekeeping duty to an
 adaptive tickless cpu
From: Peter Zijlstra <peterz@infradead.org>
To: Christoph Lameter <cl@linux.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
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Date: Tue, 27 Mar 2012 18:47:03 +0200
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On Tue, 2012-03-27 at 11:08 -0500, Christoph Lameter wrote:
> 
> I wish you would disentangle the nohz work from the cpusets. Cpusets is
> aged and being replaced by cgroups. And the cgroup work is something that
> is not suitable for many loads given the VM overhead added. 

What VM overhead? Are you talking about the memcg nonsense? That's
entirely optional, you don't need to either build that or enable it.

And if we ever get rid of that multiple hierarchy nonsense I don't see a
reason to get rid of cpuset at all. The only reason to want to replace
it is to avoid the dis-joint-ness it has with the cpu controller (and
possible the memcg one).