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From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Michael Wang <wangyun@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v5] sched: Avoid unnecessary work in reweight_entity
Date: Mon, 20 Feb 2012 14:08:31 +0100	[thread overview]
Message-ID: <1329743311.2293.341.camel@twins> (raw)
In-Reply-To: <4F3F025B.5010400@linux.vnet.ibm.com>

On Sat, 2012-02-18 at 09:43 +0800, Michael Wang wrote:
> And as reight_entity is invoked very often, I think this patch can do some help to the 
> performance, although there are no numbers, we can prove it logically :)  

Well, you're probably right (although I think you completely ignored the
optimizing compiler), but still it would be good to get some numbers to
confirm reality :-)

Just pick your favourite cgroup workload/benchmark and run a pre/post
comparison, possible using perf record.

If all squares up you should see an improvement in your benchmark score
as well as see a reduction in time spend in the function you're
patching.

  reply	other threads:[~2012-02-20 13:08 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-06  9:37 [PATCH] sched: Avoid unnecessary work in reweight_entity Michael Wang
2012-02-06 10:31 ` Michael Wang
2012-02-07  2:18 ` Michael Wang
2012-02-07  2:36   ` [PATCH v2] " Michael Wang
2012-02-08  2:10     ` [PATCH v3] sched: " Michael Wang
2012-02-16 14:14       ` [PATCH v4] " Michael Wang
2012-02-16 14:29         ` Peter Zijlstra
2012-02-17  2:28           ` Michael Wang
2012-02-17  6:03           ` [PATCH v5] " Michael Wang
2012-02-18  1:43             ` Michael Wang
2012-02-20 13:08               ` Peter Zijlstra [this message]
2012-02-23 10:40                 ` Michael Wang
2012-02-24  2:08                   ` Michael Wang
2012-02-25 13:56                     ` Michael Wang
2012-02-27  4:12                       ` Srivatsa Vaddagiri
2012-02-27  5:07                         ` Michael Wang
2012-02-27  5:10                           ` Srivatsa Vaddagiri
2012-02-27  6:21                             ` Michael Wang
2012-02-27  6:44                               ` Srivatsa Vaddagiri
2012-02-16 14:32         ` [PATCH v4] " Michael Wang

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