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Date: Thu, 16 Jan 2014 14:49:25 -0800 (PST)
From: David Rientjes <rientjes@google.com>
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To: Michal Hocko <mhocko@suse.cz>
cc: Andrew Morton <akpm@linux-foundation.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
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        linux-kernel@vger.kernel.org
Subject: Re: [patch v2 -mm] mm, oom: prefer thread group leaders for display
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On Thu, 16 Jan 2014, Michal Hocko wrote:

> > When two threads have the same badness score, it's preferable to kill the 
> > thread group leader so that the actual process name is printed to the 
> > kernel log rather than the thread group name which may be shared amongst 
> > several processes.
> 
> I am not sure I understand this. Is this about ->comm? If yes then why
> couldn't the group leader do PR_SET_NAME?
> 

Both comm and pid, we only display thread group leaders in the tasklist 
dump of eligible processes, we want the killed message to specify from 
which process.

You're suggesting a thread group leader do PR_SET_NAME of all its threads 
for readable oom killer output?  Lol.