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Date:   Sat, 15 Jun 2019 09:20:04 -0700
From:   Tejun Heo <tj@kernel.org>
To:     Xi Ruoyao <xry111@mengyan1223.wang>
Cc:     Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@kernel.org>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        cgroups@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, dschatzberg@fb.com
Subject: Re: [PATCH RFC] mm: memcontrol: add cgroup v2 interface to read
 memory watermark
Message-ID: <20190615162004.GG657710@devbig004.ftw2.facebook.com>
References: <0f1be041f8de95603753ffe989bd25069efa13bb.camel@mengyan1223.wang>
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On Sat, Jun 15, 2019 at 04:20:04PM +0800, Xi Ruoyao wrote:
> Introduce a control file memory.watermark showing the watermark
> consumption of the cgroup and its descendants, in bytes.
> 
> Signed-off-by: Xi Ruoyao <xry111@mengyan1223.wang>

Memory usage w/o pressure metric isn't all that useful and reporting
just the historical maximum of memory.current can be outright
misleading.  The use case of determining maximum amount of required
memory is legit but it needs to maintain sustained positive pressure
while taking measurements.  There are efforts on this front, so let's
not merge this one for now.

Nacked-by: Tejun Heo <tj@kernel.org>

Thanks.

-- 
tejun