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From:   Daniel Drake <drake@endlessm.com>
Date:   Tue, 17 Jul 2018 07:13:52 -0500
Message-ID: <CAD8Lp45W00ga-P-nb6iytgSGW4xwSzmaTHA87DOvSotN0S2edw@mail.gmail.com>
Subject: Re: [PATCH 0/10] psi: pressure stall information for CPU, memory, and
 IO v2
To:     Michal Hocko <mhocko@kernel.org>
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On Tue, Jul 17, 2018 at 6:25 AM, Michal Hocko <mhocko@kernel.org> wrote:
> Yes this is really unfortunate. One thing that could help would be to
> consider a trashing level during the reclaim (get_scan_count) to simply
> forget about LRUs which are constantly refaulting pages back. We already
> have the infrastructure for that. We just need to plumb it in.

Can you go into a bit more detail about that infrastructure and how we
might detect which pages are being constantly refaulted? I'm
interested in spending a few hours on this topic to see if I can come
up with anything.

Thanks
Daniel