Re: [PATCH v2 0/9] workingset protection/detection on the anonymous LRU list

From: Andrew Morton
Date: Sat Feb 29 2020 - 23:47:28 EST


On Thu, 27 Feb 2020 16:48:47 +0900 Joonsoo Kim <js1304@xxxxxxxxx> wrote:

> Hello, Andrew.
>
> > > * SOLUTION
> > > Since this is what we want to avoid, this patchset implements workingset
> > > protection. Like as the file LRU list, newly created or swap-in anonymous
> > > page is started on the inactive list. Also, like as the file LRU list,
> > > if enough reference happens, the page will be promoted. This simple
> > > modification changes the above example as following.
> >
> > One wonders why on earth we weren't doing these things in the first
> > place?
>
> I don't know. I tried to find the origin of this behaviour and found
> that it's from you 18 years ago. :)
>
> It mentions that starting pages on the active list boosts throughput on
> stupid swapstormy test but I cannot guess the exact reason of such
> improvement.
>
> Anyway, Following is the related patch history. Could you remember
> anything about it?
>

erm, yes, that was a long time ago ;) I guess enough other things have
changed since then to necessitate a revisit!