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From:   Joonsoo Kim <js1304@gmail.com>
Date:   Wed, 1 Jul 2020 15:18:12 +0900
Message-ID: <CAAmzW4P6Co3Y4KMLFps6BsZvvt2vwQ4g2bUUZCMbNy_tE40xCA@mail.gmail.com>
Subject: Re: [PATCH v6 1/6] mm/vmscan: make active/inactive ratio as 1:1 for
 anon lru
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Linux Memory Management List <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@kernel.org>,
        Hugh Dickins <hughd@google.com>,
        Minchan Kim <minchan@kernel.org>,
        Mel Gorman <mgorman@techsingularity.net>, kernel-team@lge.com,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>
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2020=EB=85=84 7=EC=9B=94 1=EC=9D=BC (=EC=88=98) =EC=98=A4=EC=A0=84 2:27, Vl=
astimil Babka <vbabka@suse.cz>=EB=8B=98=EC=9D=B4 =EC=9E=91=EC=84=B1:
>
> On 6/17/20 7:26 AM, js1304@gmail.com wrote:
> > From: Joonsoo Kim <iamjoonsoo.kim@lge.com>
> >
> > Current implementation of LRU management for anonymous page has some
> > problems. Most important one is that it doesn't protect the workingset,
> > that is, pages on the active LRU list. Although, this problem will be
> > fixed in the following patchset, the preparation is required and
> > this patch does it.
> >
> > What following patchset does is to restore workingset protection. In th=
is
>
> "Restore" sounds as if the protection used to be there and then it was re=
moved.
> If it's the case, it should be said what commit did that. Otherwise I wou=
ld say
> "implement", not "restore"?
>
> > case, newly created or swap-in pages are started their lifetime on the
>
> I would rephrase it: "After the following patch, newly created or swap-in=
 pages
> will start their lifetime... "
>
> > inactive list. If inactive list is too small, there is not enough chanc=
e
> > to be referenced and the page cannot become the workingset.
> >
> > In order to provide enough chance to the newly anonymous pages, this pa=
tch
>
> "In order to provide the newly anonymous pages enough chance to be refere=
nced
> again..."
>
> > makes active/inactive LRU ratio as 1:1.
>
> Here I would add:
>
> This is just a temporary measure. Later patch in the series introduces
> workingset detection for anonymous LRU that will be used to better decide=
 if
> pages should start on the active and inactive list. Afterwards this patch=
 is
> effectively reverted.
>
> > Acked-by: Johannes Weiner <hannes@cmpxchg.org>
> > Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
>
> Acked-by: Vlastimil Babka <vbabka@suse.cz>

Thanks!

I will change the commit description as you suggested.

Thanks.