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Date:   Fri, 18 Mar 2022 01:46:39 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     maobibo <maobibo@loongson.cn>
Cc:     Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
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        Anshuman Khandual <anshuman.khandual@arm.com>
Subject: Re: [PATCH v2] mm: add access/dirty bit on numa page fault
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On Fri, Mar 18, 2022 at 09:01:32AM +0800, maobibo wrote:
> > Is this a correctness problem, in which case this will need to be
> > backported, or is this a performance problem, in which case can you
> > share some numbers?
> It is only performance issue, and there is no obvious performance
> improvement for general workloads on my hand, but I do not test
> it on microbenchmark.

... if there's no performance improvement, why should we apply this
patch?  Confused.