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Date: Mon, 2 Nov 2015 10:12:56 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
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To: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
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Subject: Re: [patch 3/3] vmstat: Create our own workqueue
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On Sat, 31 Oct 2015, Tetsuo Handa wrote:

> Then, you need to update below description (or drop it) because
> patch 3/3 alone will not guarantee that the counters are up to date.

The vmstat system does not guarantee that the counters are up to date
always. The whole point is the deferral of updates for performance
reasons. They are updated *at some point* within stat_interval. That needs
to happen and that is what this patchset is fixing.