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Date:   Mon, 25 Apr 2022 14:09:06 +0200 (CEST)
From:   Christoph Lameter <cl@gentwo.de>
To:     Aaron Tomlin <atomlin@redhat.com>
cc:     frederic@kernel.org, mtosatti@redhat.com, tglx@linutronix.de,
        mingo@kernel.org, peterz@infradead.org, pauld@redhat.com,
        neelx@redhat.com, oleksandr@natalenko.name,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [RFC PATCH v3] tick/sched: Ensure quiet_vmstat() is called when
 the idle tick was stopped too
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On Mon, 25 Apr 2022, Aaron Tomlin wrote:

> Yes, in the context of nohz, this patch should ensure it, if required, when
> the idle tick is to be stopped.

What I said was that it is generally useful. Even in the non NOHZ case.

Folding the vmstat diffs *always* when entering idle prevents unnecessary
wakeups and processing in the future and also provides more accurate
counters for the VM allowing better decision to be made on reclaim.