From: Michal Hocko <mhocko@kernel.org>
To: David Hildenbrand <david@redhat.com>
Cc: Yafang Shao <laoar.shao@gmail.com>,
hannes@cmpxchg.org, vdavydov.dev@gmail.com,
akpm@linux-foundation.org, linux-mm@kvack.org
Subject: Re: [PATCH v2] mm, memcg: avoid oom if cgroup is not populated
Date: Wed, 27 Nov 2019 12:41:25 +0100 [thread overview]
Message-ID: <20191127114125.GO20912@dhcp22.suse.cz> (raw)
In-Reply-To: <a036686e-8d17-acf5-125b-162464f1d775@redhat.com>
On Wed 27-11-19 12:11:24, David Hildenbrand wrote:
[...]
> 4. This patch on its own (if there are no processes, there is nothing to
> kill) does not sound too wrong to me. Instead of an endless loop
> (besides signals) where we can't make any progress, we exit right away.
mem_cgroup_out_of_memory returns false when there is no oom victim
selected and then we break out.
My main objection to the patch is that it adds a subtle inconsitency.
Admins are simply not going to see that the memcg was OOM due to the
limit change and OOM killer cannot do anything about that. No tasks vs.
no killable task doesn't make any real difference. There is simply no
way to get out of that situation.
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2019-11-27 11:41 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-27 1:28 Yafang Shao
2019-11-27 8:54 ` Michal Hocko
2019-11-27 9:17 ` Yafang Shao
2019-11-27 9:33 ` Yafang Shao
2019-11-27 11:11 ` David Hildenbrand
2019-11-27 11:35 ` Yafang Shao
2019-11-27 11:58 ` Michal Hocko
2019-11-27 12:01 ` Yafang Shao
2019-11-27 11:41 ` Michal Hocko [this message]
2019-11-27 11:55 ` Yafang Shao
2019-11-27 11:57 ` David Hildenbrand
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