Re: [PATCH] memcg: oom: ignore oom warnings from memory.max

From: Johannes Weiner
Date: Thu Apr 30 2020 - 15:29:21 EST


On Thu, Apr 30, 2020 at 11:27:12AM -0700, Shakeel Butt wrote:
> Lowering memory.max can trigger an oom-kill if the reclaim does not
> succeed. However if oom-killer does not find a process for killing, it
> dumps a lot of warnings.
>
> Deleting a memcg does not reclaim memory from it and the memory can
> linger till there is a memory pressure. One normal way to proactively
> reclaim such memory is to set memory.max to 0 just before deleting the
> memcg. However if some of the memcg's memory is pinned by others, this
> operation can trigger an oom-kill without any process and thus can log a
> lot un-needed warnings. So, ignore all such warnings from memory.max.

Can't you set memory.high=0 instead? It does the reclaim portion of
memory.max, without the actual OOM killing that causes you problems.