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Date:   Tue, 15 Oct 2019 13:04:01 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc:     linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, cgroups@vger.kernel.org,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Johannes Weiner <hannes@cmpxchg.org>
Subject: Re: [PATCH] mm/memcontrol: update lruvec counters in
 mem_cgroup_move_account
Message-ID: <20191015110401.GZ317@dhcp22.suse.cz>
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On Tue 15-10-19 13:49:14, Konstantin Khlebnikov wrote:
> On 15/10/2019 13.36, Michal Hocko wrote:
> > On Tue 15-10-19 11:44:22, Konstantin Khlebnikov wrote:
> > > On 15/10/2019 11.20, Michal Hocko wrote:
> > > > On Tue 15-10-19 11:09:59, Konstantin Khlebnikov wrote:
> > > > > Mapped, dirty and writeback pages are also counted in per-lruvec stats.
> > > > > These counters needs update when page is moved between cgroups.
> > > > 
> > > > Please describe the user visible effect.
> > > 
> > > Surprisingly I don't see any users at this moment.
> > > So, there is no effect in mainline kernel.
> > 
> > Those counters are exported right? Or do we exclude them for v1?
> 
> It seems per-lruvec statistics is not exposed anywhere.
> And per-lruvec NR_FILE_MAPPED, NR_FILE_DIRTY, NR_WRITEBACK never had users.

So why do we have it in the first place? I have to say that counters
as we have them now are really clear as mud. This is really begging for
a clean up.
-- 
Michal Hocko
SUSE Labs