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Date:   Tue, 21 May 2019 12:34:33 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Anshuman Khandual <anshuman.khandual@arm.com>
Cc:     Tim Murray <timmurray@google.com>,
        Minchan Kim <minchan@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Joel Fernandes <joel@joelfernandes.org>,
        Suren Baghdasaryan <surenb@google.com>,
        Daniel Colascione <dancol@google.com>,
        Shakeel Butt <shakeelb@google.com>,
        Sonny Rao <sonnyrao@google.com>,
        Brian Geffon <bgeffon@google.com>
Subject: Re: [RFC 0/7] introduce memory hinting API for external process
Message-ID: <20190521103433.GL32329@dhcp22.suse.cz>
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On Tue 21-05-19 08:25:55, Anshuman Khandual wrote:
> On 05/20/2019 10:29 PM, Tim Murray wrote:
[...]
> > not seem to introduce a noticeable hot start penalty, not does it
> > cause an increase in performance problems later in the app's
> > lifecycle. I've measured with and without process_madvise, and the
> > differences are within our noise bounds. Second, because we're not
> 
> That is assuming that post process_madvise() working set for the application is
> always smaller. There is another challenge. The external process should ideally
> have the knowledge of active areas of the working set for an application in
> question for it to invoke process_madvise() correctly to prevent such scenarios.

But that doesn't really seem relevant for the API itself, right? The
higher level logic the monitor's business.
-- 
Michal Hocko
SUSE Labs