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Date:   Mon, 6 Jan 2020 13:24:36 +0000
From:   Chris Down <chris@chrisdown.name>
To:     Michal Hocko <mhocko@kernel.org>
Cc:     Hui Zhu <teawater@gmail.com>, hannes@cmpxchg.org,
        vdavydov.dev@gmail.com, akpm@linux-foundation.org,
        linux-kernel@vger.kernel.org, cgroups@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [RFC] memcg: Add swappiness to cgroup2
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Michal Hocko writes:
>I am not really sure I agree here though. Swappiness has been
>traditionally more about workload because it has been believed that it
>is a preference of the workload whether the anonymous or disk based
>memory is more important. Whether this is a good interface is debatable
>of course but time has shown that it is extremely hard to tune.

Sure, it can theoretically be hardware- and workload-specific -- I don't think 
we disagree here. The reason I suggest it's a generally hardware-specific 
tunable rather than a workload-specific tunable is it's pretty rare to see 
anyone who's meaningfully used it for workload-specific tuning :-)