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Date:   Thu, 25 Jan 2018 09:11:34 +0100
From:   Michal Hocko <mhocko@kernel.org>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     David Rientjes <rientjes@google.com>, Tejun Heo <tj@kernel.org>,
        Roman Gushchin <guro@fb.com>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        kernel-team@fb.com, cgroups@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [patch -mm 3/4] mm, memcg: replace memory.oom_group with policy
 tunable
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On Wed 24-01-18 14:08:05, Andrew Morton wrote:
[...]
> Can we please try to narrow the scope of this issue by concentrating on
> the userspace interfaces?  David believes that the mount option and
> memory.oom_group will disappear again in the near future, others
> disagree.

Mount option is the cgroups maintainers call. And they seemed to be OK
with it.
I've tried to explain that oom_group is something that is semantically
sane and something we want to support because there are workloads which
simply do not work properly when only a subset is torn down. As such it
is not an API hazard AFAICS.
-- 
Michal Hocko
SUSE Labs