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Message-ID: <1358752180.4994.65.camel@marge.simpson.net>
Subject: Re: [RFC PATCH 0/2] sched: simplify the select_task_rq_fair()
From: Mike Galbraith <bitbucket@online.de>
To: Michael Wang <wangyun@linux.vnet.ibm.com>
Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org,
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Date: Mon, 21 Jan 2013 08:09:40 +0100
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On Mon, 2013-01-21 at 07:42 +0100, Mike Galbraith wrote: 
> On Mon, 2013-01-21 at 13:07 +0800, Michael Wang wrote:

> > May be we could try change this back to the old way later, after the aim
> > 7 test on my server.
> 
> Yeah, something funny is going on.

Never entering balance path kills the collapse.  Asking wake_affine()
wrt the pull as before, but allowing us to continue should no idle cpu
be found, still collapsed.  So the source of funny behavior is indeed in
balance_path.

-Mike