From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH v2 3/3] mm: memcontrol: recursive memory.low protection
Date: Fri, 14 Feb 2020 12:17:04 -0500
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To: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>, Andrew Morton <akpm@linux-foundation.org>, Roman Gushchin <guro@fb.com>, linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com

On Fri, Feb 14, 2020 at 11:53:11AM -0500, Johannes Weiner wrote:
> However, what you've really done just now is flattened the resource
> hierarchy. You configured the_workload not just more important than
> its sibling "misc", but you actually pulled it up the resource tree
> and declared it more important than what's running in other sessions,
> what users are running, and even the system software. Your cgroup tree
> still reflects process ownership, but it doesn't actually reflect the
> resource hierarchy you just configured.

Just to second this point, anything moving in this direction will be a
hard nack from me. We don't want use_hierarchy for cgroup2 and I'm
baffled that this is even being suggested seriously. If we have
learned *anything* from cgroup1's mistakes, this should be the one.

Thanks.

-- 
tejun