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From:   Suleiman Souhlal <suleiman@google.com>
Date:   Thu, 19 Sep 2019 22:39:18 +0900
Message-ID: <CABCjUKByipk2e1Hh1_PwC+p2Fig=6RMfd0zBeVQtyn5Y48gYXQ@mail.gmail.com>
Subject: Re: [PATCH RFC 00/14] The new slab memory controller
To:     Roman Gushchin <guro@fb.com>
Cc:     linux-mm@kvack.org, Michal Hocko <mhocko@kernel.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        kernel-team@fb.com, Shakeel Butt <shakeelb@google.com>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Waiman Long <longman@redhat.com>
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On Fri, Sep 6, 2019 at 6:57 AM Roman Gushchin <guro@fb.com> wrote:
> The patchset has been tested on a number of different workloads in our
> production. In all cases, it saved hefty amounts of memory:
> 1) web frontend, 650-700 Mb, ~42% of slab memory
> 2) database cache, 750-800 Mb, ~35% of slab memory
> 3) dns server, 700 Mb, ~36% of slab memory

Do these workloads cycle through a lot of different memcgs?

For workloads that don't, wouldn't this approach potentially use more
memory? For example, a workload where everything is in one or two
memcgs, and those memcgs last forever.

-- Suleiman