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Date:   Mon, 25 Nov 2019 22:46:03 +0800
From:   Pengfei Li <fly@kernel.page>
To:     Michal Hocko <mhocko@kernel.org>
Cc:     akpm@linux-foundation.org, mgorman@techsingularity.net,
        vbabka@suse.cz, cl@linux.com, iamjoonsoo.kim@lge.com, guro@fb.com,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org, fly@kernel.page
Subject: Re: [RFC v1 00/19] Modify zonelist to nodelist v1
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On Mon, 25 Nov 2019 09:40:58 +0100
Michal Hocko <mhocko@kernel.org> wrote:

> On Fri 22-11-19 23:05:43, Pengfei Li wrote:
> > On Thu, 21 Nov 2019 19:04:01 +0100
> > Michal Hocko <mhocko@kernel.org> wrote:
> > 
> > > On Thu 21-11-19 23:17:52, Pengfei Li wrote:
> > > [...]
> > > > Since I don't currently have multiple node NUMA systems, I
> > > > would be grateful if anyone would like to test this series of
> > > > patches.
> > > 
> > > I didn't really get to think about the actual patchset. From a
> > > very quick glance I am wondering whether we need to optimize as
> > > there are usually only small amount of numa nodes. But I am quite
> > > busy so I cannot really do any claims.
> > 
> > Thanks for your comments.
> > 
> > I think it's time to modify the zonelist to nodelist because the
> > zonelist is always in node order and the page reclamation is based
> > on node.
> > 
> > I will do more performance testing to show that multi-node systems
> > will benefit from this series of patches.
> 
> Sensible performance numbers on multiple workloads (ideally some real
> world ones rather than artificial microbenchmarks) is essential for a
> performance optimization that is this large.


Thank you for your suggestion.

But this is probably a bit difficult because I don't have a NUMA server
to do real-world workload testing.

I will do as many performance benchmarks as possible, just like Mel
Gorman's "Move LRU page reclaim from zones to nodes v9"
(https://lwn.net/Articles/694121/).


-- 
Pengfei