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Date: Mon, 26 Sep 2011 10:35:55 +0200
From: Michal Hocko <mhocko@suse.cz>
Subject: [PATCH 2/2] oom: give bonus to frozen processes
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To: David Rientjes <rientjes@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>, Konstantin Khlebnikov <khlebnikov@openvz.org>, linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org, KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>, KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>, "Rafael J. Wysocki" <rjw@sisk.pl>

On Fri 26-08-11 11:13:40, David Rientjes wrote:
> On Fri, 26 Aug 2011, Michal Hocko wrote:
[...]
> > I am not saying the bonus is necessary, though. It depends on what
> > the freezer is used for (e.g. freeze a process which went wild and
> > debug what went wrong wouldn't welcome that somebody killed it or other
> > (mis)use which relies on D state).
[...]
> If it actually does come down to a heuristic change, then it need not 
> happen in the oom killer: the freezing code would need to use 
> test_set_oom_score_adj() to temporarily reduce the oom_score_adj for that 
> task until it comes out of the refrigerator.  We already use that in ksm 
> and swapoff to actually prefer threads, but we can use it to bias against 
> threads as well.

Let's try it with a heuristic change first. If you really do not like
it, we can move to oom_scode_adj. I like the heuristic change little bit
more because it is at the same place as the root bonus.
---