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Sender: Tejun Heo <htejun@gmail.com>
Date:   Mon, 8 Feb 2021 11:02:55 -0500
From:   Tejun Heo <tj@kernel.org>
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     Shakeel Butt <shakeelb@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Michal Hocko <mhocko@suse.com>, Roman Gushchin <guro@fb.com>,
        Linux MM <linux-mm@kvack.org>,
        Cgroups <cgroups@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Kernel Team <kernel-team@fb.com>
Subject: Re: [PATCH 7/8] mm: memcontrol: consolidate lruvec stat flushing
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Hello,

On Mon, Feb 08, 2021 at 03:54:14PM -0500, Johannes Weiner wrote:
> We probably do need a better solution for the lruvecs as well, but in
> this case it just started holding up fixing the memory.stat issue for
> no reason and so I tabled it for another patch series.

rstat doesn't currently have a flush throttling mechanism cuz it doens't
expect readers to be super hot but adding one should be pretty easy - e.g.
it can just keep track of the number of updates on this cpu since the last
flush and then flush iff the it's above a certain threshold. Shouldn't be
too difficult to match or exceed the performance and error characteristics
of the existing code.

Thanks.

-- 
tejun