linux-kernel - Re: [patch -mm v2] mm: introduce oom_adj

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <6599ad830908030917v6c70ec01ke2ed15f0fb627f9@mail.gmail.com>
Date:	Mon, 3 Aug 2009 09:17:01 -0700
From:	Paul Menage <menage@...gle.com>
To:	David Rientjes <rientjes@...gle.com>
Cc:	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Rik van Riel <riel@...hat.com>,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org
Subject: Re: [patch -mm v2] mm: introduce oom_adj_child

On Sat, Aug 1, 2009 at 1:26 PM, David Rientjes<rientjes@...gle.com> wrote:
>
> It's more likely than not that applications were probably written to the
> way the documentation described the two files: that is, adjust
> /proc/pid/oom_score by tuning /proc/pid/oom_adj

I'd actually be pretty surprised if anyone was really doing that -
don't forget that the oom_score is something that varies dynamically
depending on things like the VM size of the process, its running time,
the VM sizes of its children, etc. So tuning oom_adj based on
oom_score will be rapidly out of date. AFAIK, oom_score was added
initially as a way to debug the OOM killer, and oom_adj was added
later as an additional knob. My suspicion is that any automated users
of oom_adj are working along the lines of

http://www.google.com/codesearch/p?hl=en&sa=N&cd=4&ct=rc#X7-oBZ_RyNM/src/server/memory/base/oommanager.cpp&q=oom_score

which just uses the values -16, 0 or 15, depending on whether the
process is critical, important or expendable.

Paul
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/