linux-kernel - Re: [PATCH 1/1] mm, oom_adj: don't loop through tasks in __set_oom

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

Message-ID: <42d5645e-0364-c8cd-01dc-93a9aaff5b09@i-love.sakura.ne.jp>
Date:   Thu, 20 Aug 2020 23:26:29 +0900
From:   Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>
To:     Michal Hocko <mhocko@...e.com>,
        Christian Brauner <christian.brauner@...ntu.com>
Cc:     "Eric W. Biederman" <ebiederm@...ssion.com>,
        Suren Baghdasaryan <surenb@...gle.com>, timmurray@...gle.com,
        mingo@...nel.org, peterz@...radead.org, tglx@...utronix.de,
        esyr@...hat.com, christian@...lner.me, areber@...hat.com,
        shakeelb@...gle.com, cyphar@...har.com, oleg@...hat.com,
        adobriyan@...il.com, akpm@...ux-foundation.org,
        gladkov.alexey@...il.com, walken@...gle.com,
        daniel.m.jordan@...cle.com, avagin@...il.com,
        bernd.edlinger@...mail.de, john.johansen@...onical.com,
        laoar.shao@...il.com, minchan@...nel.org, kernel-team@...roid.com,
        linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
        linux-mm@...ck.org
Subject: Re: [PATCH 1/1] mm, oom_adj: don't loop through tasks in
 __set_oom_adj when not necessary

On 2020/08/20 23:15, Michal Hocko wrote:
> I would tend to agree that from the userspace POV it is nice to look at
> oom tuning per process but fundamentaly the oom killer operates on the
> address space much more than other resources bound to a process because
> it is usually the address space hogging the largest portion of the
> memory footprint. This is the reason why the oom killer has been
> evaluating tasks based on that aspect rather than other potential memory
> consumers bound to a task. Mostly due to lack of means to evaluate
> those.

We already allow specifying potential memory consumers via oom_task_origin().

If we change from a property of the task/thread-group to a property of mm,
we won't be able to add means to adjust oom score based on other potential
memory consumers bound to a task (e.g. pipes) in the future.