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Subject: Re: [PATCH] Add tracepoints to track pagecache transition
From: Peter Zijlstra <peterz@infradead.org>
To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Atsushi Tsuji <a-tsuji@bk.jp.nec.com>, linux-kernel@vger.kernel.org,
       Jason Baron <jbaron@redhat.com>, Ingo Molnar <mingo@elte.hu>,
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Date: Tue, 17 Feb 2009 12:54:11 +0100
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On Tue, 2009-02-17 at 20:38 +0900, KOSAKI Motohiro wrote:
> If you want to see I/O activity, you need to add tracepoint into block
> layer.

We already have that, Arnaldo converted blktrace to use tracepoints and
wrote an ftrace tracer for it.