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From: Andi Kleen <ak@linux.intel.com>
To: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <andi@firstfloor.org>,
	Arnaldo Carvalho de Melo <acme@infradead.org>,
	Ingo Molnar <mingo@kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Namhyung Kim <namhyung@kernel.org>, Jiri Olsa <jolsa@redhat.com>
Subject: Re: [PATCH] tools, perf: Allow the user to disable time stamps
Date: Tue, 25 Mar 2014 14:01:09 -0700	[thread overview]
Message-ID: <20140325210109.GH15074@tassilo.jf.intel.com> (raw)
In-Reply-To: <CABPqkBSpoc1LX3=hZTnwM9KAeu943kbS0UgCbupWJf1idtdWNg@mail.gmail.com>

> 
> Timestamp are useful to order samples during reporting.
> How do you do with it if you monitor multi-threaded (multi-cpu)
> workloads. This is only good for single thread or single CPU
> measurements. Or am I missing something?

For a perf report order doesn't matter (except against mmaps)
The CPUs are still separated of course

You're right for some special analysis it matters, that is why
it is only an option. 

But for the standard "only care about perf report and 
don't care about about program startup" case it's a nice saving.

-Andi

  reply	other threads:[~2014-03-25 21:01 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-03-25 20:44 [PATCH] tools, perf: Allow the user to disable time stamps Andi Kleen
2014-03-25 20:54 ` Stephane Eranian
2014-03-25 21:01   ` Andi Kleen [this message]
2014-03-25 22:15     ` Stephane Eranian
2014-03-25 22:34       ` Andi Kleen
2014-03-25 21:06   ` Andi Kleen
  -- strict thread matches above, loose matches on Subject: below --
2014-03-25 20:34 Andi Kleen

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