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Date: Thu, 25 Jan 2018 01:54:41 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Shakeel Butt <shakeelb@google.com>
Cc: Amir Goldstein <amir73il@gmail.com>, Jan Kara <jack@suse.cz>,
        Yang Shi <yang.s@alibaba-inc.com>, Michal Hocko <mhocko@kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux MM <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] fs: fsnotify: account fsnotify metadata to kmemcg
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On Wed, Jan 24, 2018 at 05:08:27PM -0800, Shakeel Butt wrote:
> First, let me apologize, I think I might have led the discussion in
> wrong direction by giving one wrong information. The current upstream
> kernel, from the syscall context, does not invoke oom-killer when a
> memcg hits its limit and fails to reclaim memory, instead ENOMEM is
> returned. The memcg oom-killer is only invoked on page faults. However
> in a separate effort I do plan to converge the behavior, long
> discussion at <https://patchwork.kernel.org/patch/9988063/>.

Correct me if I'm misinterpreting you, but your rationale in there
appears to be along the lines of "userland applications might not
be ready to handle -ENOMEM gracefully, so let's hit them with
kill -9 instead - that will be handled properly, 'cuz M4G1C!!1!!!!"

I must admit that I like the general feel of that idea; may I suggest,
as a modest improvement, appending "/usr/local/bin/self-LART\n"
to the end of $HOME/.bashrc as well?  Killing luser's processes is
a nice start, but you have to allow for local policies...

-- 
WWSimonDo?