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Date:   Mon, 21 Oct 2019 18:09:02 +0000 (UTC)
From:   Christopher Lameter <cl@linux.com>
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To:     Roman Gushchin <guro@fb.com>
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        Michal Hocko <mhocko@kernel.org>,
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        Shakeel Butt <shakeelb@google.com>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Waiman Long <longman@redhat.com>
Subject: Re: [PATCH 02/16] mm: vmstat: use s32 for vm_node_stat_diff in struct
 per_cpu_nodestat
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On Mon, 21 Oct 2019, Roman Gushchin wrote:

> Sp far I haven't noticed any regression on the set of workloads where I did test
> the patchset, but if you know any benchmark or realistic test which can affected
> by this check, I'll be happy to try.
>
> Also, less-than-word-sized operations can be slower on some platforms.

The main issue in the past was the cache footprint. Memory is slow.
Processors are fast.