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Date: Thu, 4 Aug 2016 11:01:24 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: kernel test robot <xiaolong.ye@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Mike Galbraith <efault@gmx.de>, Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>, lkp@01.org
Subject: Re: [lkp] [sched/fair]  e210bffd39: perf-stat.cpu-migrations -36.0%
 decrease
Message-ID: <20160804090124.GK6879@twins.programming.kicks-ass.net>
References: <20160804052423.GA26201@yexl-desktop>
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On Thu, Aug 04, 2016 at 01:24:23PM +0800, kernel test robot wrote:
> 
> FYI, we noticed perf-stat.cpu-migrations -36.0% decrease due to commit:
> 
> commit e210bffd39d01b649c94b820c28ff112673266dd ("sched/fair: Fix and optimize the fork() path")
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> 
> in testcase: unixbench
> on test machine: 16 threads Broadwell-DE with 8G memory
> with following parameters:
> 
> 	runtime: 300s
> 	nr_task: 1
> 	test: shell8
> 	cpufreq_governor: performance
> 
> 

Urgh, I so hate these reports. They're near useless :/

It took me 3 readings to realize it was the unixbench testcase (why
isn't that in the subject!?). But then I still haven't found the primary
performance metric. Does the test improve, degrade or not change
overall?