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From: Shakeel Butt <shakeelb@google.com>
Date: Mon, 30 Oct 2017 12:28:13 -0700
Message-ID: <CALvZod65sU+wujxAR9AqTdbMHkHsMsOyfNXYf1t=w1BEpx5LHw@mail.gmail.com>
Subject: Re: [PATCH] fs, mm: account filp and names caches to kmemcg
To: Michal Hocko <mhocko@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>, Greg Thelen <gthelen@google.com>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linux MM <linux-mm@kvack.org>, linux-fsdevel@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>
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On Mon, Oct 30, 2017 at 1:29 AM, Michal Hocko <mhocko@kernel.org> wrote:
> On Fri 27-10-17 13:50:47, Shakeel Butt wrote:
>> > Why is OOM-disabling a thing? Why isn't this simply a "kill everything
>> > else before you kill me"? It's crashing the kernel in trying to
>> > protect a userspace application. How is that not insane?
>>
>> In parallel to other discussion, I think we should definitely move
>> from "completely oom-disabled" semantics to something similar to "kill
>> me last" semantics. Is there any objection to this idea?
>
> Could you be more specific what you mean?
>

I get the impression that the main reason behind the complexity of
oom-killer is allowing processes to be protected from the oom-killer
i.e. disabling oom-killing a process by setting
/proc/[pid]/oom_score_adj to -1000. So, instead of oom-disabling, add
an interface which will let users/admins to set a process to be
oom-killed as a last resort.