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Date: Tue, 5 Jun 2012 09:40:28 -0500 (CDT)
From: Christoph Lameter <cl@linux.com>
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To: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
cc: Pekka Enberg <penberg@kernel.org>,
        Anton Vorontsov <anton.vorontsov@linaro.org>,
        Minchan Kim <minchan@kernel.org>,
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        linux-kernel@vger.kernel.org, linaro-kernel@lists.linaro.org,
        patches@linaro.org, kernel-team@android.com
Subject: Re: [PATCH 3/3] vmevent: Implement special low-memory attribute
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On Tue, 8 May 2012, KOSAKI Motohiro wrote:

> 4) Currently, vmstat have per-cpu batch and vmstat updating makes 3
> second delay at maximum.

Nope. The delay is one second only and it is limited to a certain amount
per cpu. There is a bound on the inaccuracy of the counter. If you want to
have them more accurate then the right approach is to limit the
threshhold. The more accurate the higher the impact of cache line
bouncing.