Date: Thu, 7 Sep 2017 11:21:22 -0500 (CDT)
From: Christopher Lameter <cl@linux.com>
To: Michal Hocko <mhocko@kernel.org>
cc: Roman Gushchin <guro@fb.com>, linux-mm@kvack.org,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>,
        David Rientjes <rientjes@google.com>,
        Andrew Morton <akpm@linux-foundation.org>, Tejun Heo <tj@kernel.org>,
        kernel-team@fb.com, cgroups@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [v7 5/5] mm, oom: cgroup v2 mount option to disable cgroup-aware
 OOM killer
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On Tue, 5 Sep 2017, Michal Hocko wrote:

> I would argue that we should simply deprecate and later drop the sysctl.
> I _strongly_ suspect anybody is using this. If yes it is not that hard
> to change the kernel command like rather than select the sysctl. The
> deprecation process would be
> 	- warn when somebody writes to the sysctl and check both boot
> 	  and sysctl values
> 	[ wait some time ]
> 	- keep the sysctl but return EINVAL
> 	[ wait some time ]
> 	- remove the sysctl

Note that the behavior that would be enabled by the sysctl is the default
behavior for the case of a constrained allocation. If a process does an
mbind to numa node 3 and it runs out of memory then that process should be
killed and the rest is fine.