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From: Peter Zijlstra <peterz@infradead.org>
To: Stephane Eranian <eranian@google.com>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>,
	linux-kernel@vger.kernel.org, mingo@elte.hu, paulus@samba.org,
	davem@davemloft.net, fweisbec@gmail.com,
	perfmon2-devel@lists.sf.net, eranian@gmail.com
Subject: Re: [RFC] perf/perf_events: misleading number of samples due to mmap()
Date: Wed, 16 Jun 2010 16:54:12 +0200	[thread overview]
Message-ID: <1276700052.1745.600.camel@laptop> (raw)
In-Reply-To: <AANLkTikvExLi_MahU3kkX1TQKvBODq8SyTSXgpyAjOay@mail.gmail.com>

On Wed, 2010-06-16 at 16:40 +0200, Stephane Eranian wrote:
> The reason is that perf reports an estimate based on the
> number of bytes written to the buffer divided by the minimal
> sample size of 24 bytes. 

Right, we should change that based on the PERF_SAMPLE flags used. It
will remain an estimate due to the out of band events, but it should be
closer than assuming the minimal sample size.

      parent reply	other threads:[~2010-06-16 14:54 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-06-16 14:40 [RFC] perf/perf_events: misleading number of samples due to mmap() Stephane Eranian
2010-06-16 14:52 ` Peter Zijlstra
2010-06-16 16:41   ` stephane eranian
2010-06-16 17:15     ` stephane eranian
2010-06-16 17:43     ` Peter Zijlstra
2010-06-16 14:54 ` Peter Zijlstra [this message]

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