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Subject: Re: Misleading OOM messages
From: Dave Hansen <dave@linux.vnet.ibm.com>
To: Christoph Lameter <cl@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>, David Rientjes <rientjes@google.com>,
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Date: Fri, 15 May 2009 11:15:07 -0700
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On Fri, 2009-05-15 at 13:57 -0400, Christoph Lameter wrote:
> > If you misconfigured cgroups, you give more memory to them.
> 
> If you do not have enough memory in a cgroup then your application should
> slow down (because of page evictions) but the system should not OOM.
> Are cgroups broken or why are you getting OOMs when using them?

See mm/oom_kill.c::mem_cgroup_out_of_memory().  A group itself can have
an OOM done on it.  It's not a system-wide oom.  We just need to ensure
that we continue to differentiate the cgroup-specific oom message from
the general one.  Maybe also include some more cgroup info in the debug
outbut.

-- Dave