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Subject: memcg: fix fatal livelock in kswapd
From: James Bottomley <James.Bottomley@HansenPartnership.com>
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Date: Mon, 02 May 2011 15:07:29 -0500
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To: Chris Mason <chris.mason@oracle.com>, linux-fsdevel <linux-fsdevel@vger.kernel.org>, linux-mm <linux-mm@kvack.org>, linux-kernel <linux-kernel@vger.kernel.org>, Paul Menage <menage@google.com>, Li Zefan <lizf@cn.fujitsu.com>, containers@lists.linux-foundation.org

The fatal livelock in kswapd, reported in this thread:

http://marc.info/?t=130392066000001

Is mitigateable if we prevent the cgroups code being so aggressive in
its zone shrinking (by reducing it's default shrink from 0 [everything]
to DEF_PRIORITY [some things]).  This will have an obvious knock on
effect to cgroup accounting, but it's better than hanging systems.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>

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