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Date:   Wed, 24 May 2023 14:30:39 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     David Hildenbrand <david@redhat.com>
Cc:     "Huang, Ying" <ying.huang@intel.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Arjan Van De Ven <arjan@linux.intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mel Gorman <mgorman@techsingularity.net>,
        Vlastimil Babka <vbabka@suse.cz>,
        Johannes Weiner <jweiner@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Pavel Tatashin <pasha.tatashin@soleen.com>,
        Matthew Wilcox <willy@infradead.org>
Subject: Re: [RFC 0/6] mm: improve page allocator scalability via splitting
 zones
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[Sorry for late reply, conferencing last 2 weeks and now catching up]

On Tue 16-05-23 12:30:21, David Hildenbrand wrote:
[...]
> > And auto-tuning doesn't sound easy.  Do you have some idea of how to do
> > that?
> 
> If we could avoid instantiating more zones and rather improve existing
> mechanisms (PCP), that would be much more preferred IMHO. I'm sure it's not
> easy, but that shouldn't stop us from trying ;)

Absolutely agreed. Increasing the zone number sounds like a hack to me
TBH. It seems like an easier way but it allows more subtle problems
later on. E.g. hard to predict per-zone memory consumption and memory
reclaim disbalances.
-- 
Michal Hocko
SUSE Labs