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Date:   Wed, 3 Jul 2019 08:56:28 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Waiman Long <longman@redhat.com>
Cc:     Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Jonathan Corbet <corbet@lwn.net>,
        Luis Chamberlain <mcgrof@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Vladimir Davydov <vdavydov.dev@gmail.com>, linux-mm@kvack.org,
        linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
        Roman Gushchin <guro@fb.com>,
        Shakeel Butt <shakeelb@google.com>,
        Andrea Arcangeli <aarcange@redhat.com>
Subject: Re: [PATCH] mm, slab: Extend slab/shrink to shrink all the memcg
 caches
Message-ID: <20190703065628.GK978@dhcp22.suse.cz>
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On Tue 02-07-19 14:37:30, Waiman Long wrote:
> Currently, a value of '1" is written to /sys/kernel/slab/<slab>/shrink
> file to shrink the slab by flushing all the per-cpu slabs and free
> slabs in partial lists. This applies only to the root caches, though.
> 
> Extends this capability by shrinking all the child memcg caches and
> the root cache when a value of '2' is written to the shrink sysfs file.

Why do we need a new value for this functionality? I would tend to think
that skipping memcg caches is a bug/incomplete implementation. Or is it
a deliberate decision to cover root caches only?
-- 
Michal Hocko
SUSE Labs