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From: Peter Zijlstra <peterz@infradead.org>
To: Glauber Costa <glommer@parallels.com>
Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org,
	devel@openvz.org, Paul Turner <pjt@google.com>,
	Tejun Heo <tj@kernel.org>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	handai.szj@gmail.com, Andrew.Phillips@lmax.com,
	Serge Hallyn <serge.hallyn@canonical.com>
Subject: Re: [PATCH v3 4/6] add a new scheduler hook for context switch
Date: Wed, 30 May 2012 13:40:51 +0200	[thread overview]
Message-ID: <1338378051.26856.267.camel@twins> (raw)
In-Reply-To: <1338376851.26856.260.camel@twins>

On Wed, 2012-05-30 at 13:20 +0200, Peter Zijlstra wrote:
> 
> $ perf stat -e cycles --repeat 100 perf bench sched messaging -p -g 100
> 
>     48,826,146,710 cycles  #    2.470 GHz  ( +-  0.17% )
>        2.149005270 seconds time elapsed    ( +-  0.12% ) 

A repeat count of 250 dropped it down to:

        2.144582157 seconds time elapsed    ( +-  0.08% )

Also, if you're poking at the context switch path, something like:

$ taskset 1 perf stat -e cycles --repeat 10 perf bench sched pipe -l 100000

gives a good number and is usually more stable than hackbench.

  reply	other threads:[~2012-05-30 11:41 UTC|newest]

Thread overview: 36+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-30  9:48 [PATCH v3 0/6] per cgroup /proc/stat statistics Glauber Costa
2012-05-30  9:48 ` [PATCH v3 1/6] measure exec_clock for rt sched entities Glauber Costa
2012-05-30 10:29   ` Peter Zijlstra
2012-05-30 10:32     ` Glauber Costa
2012-05-30 10:42       ` Peter Zijlstra
2012-05-30 10:42         ` Glauber Costa
2012-05-30 11:00           ` Paul Turner
2012-05-30 12:09             ` Glauber Costa
2012-05-30  9:48 ` [PATCH v3 2/6] account guest time per-cgroup as well Glauber Costa
2012-05-30 10:32   ` Peter Zijlstra
2012-05-30 10:36     ` Glauber Costa
2012-05-30 10:46       ` Paul Turner
2012-05-30  9:48 ` [PATCH v3 3/6] expose fine-grained per-cpu data for cpuacct stats Glauber Costa
2012-05-30 10:34   ` Peter Zijlstra
2012-05-30 10:34     ` Glauber Costa
2012-05-30 10:43       ` Peter Zijlstra
2012-05-30 10:44         ` Glauber Costa
2012-05-30 11:24           ` Peter Zijlstra
2012-05-30 11:24   ` Paul Turner
2012-05-30 12:20     ` Glauber Costa
2012-05-30 12:48       ` Paul Turner
2012-05-30 12:52         ` Glauber Costa
2012-05-30 13:26         ` Glauber Costa
2012-05-30 13:26         ` Glauber Costa
2012-05-30  9:48 ` [PATCH v3 4/6] add a new scheduler hook for context switch Glauber Costa
2012-05-30 11:20   ` Peter Zijlstra
2012-05-30 11:40     ` Peter Zijlstra [this message]
2012-05-30 12:08       ` Glauber Costa
2012-05-30 12:07     ` Glauber Costa
2012-05-30  9:48 ` [PATCH v3 5/6] Also record sleep start for a task group Glauber Costa
2012-05-30 11:35   ` Paul Turner
2012-05-30 12:24     ` Glauber Costa
2012-05-30 12:44       ` Peter Zijlstra
2012-05-30 12:44         ` Glauber Costa
2012-05-30  9:48 ` [PATCH v3 6/6] expose per-taskgroup schedstats in cgroup Glauber Costa
2012-05-30 11:22   ` Peter Zijlstra

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