Date: Tue, 11 Oct 2016 11:39:57 +0100
From: Matt Fleming <matt@codeblueprint.co.uk>
To: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>,
        Wanpeng Li <kernellwp@gmail.com>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Mike Galbraith <umgwanakikbuti@gmail.com>,
        Yuyang Du <yuyang.du@intel.com>
Subject: Re: [PATCH] sched/fair: Do not decay new task load on first enqueue
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On Tue, 11 Oct, at 10:44:25AM, Dietmar Eggemann wrote:
> 
> [...]
> 
> Yeah, you're right. But I can't see any significant difference. IMHO,
> it's all in the noise.
> 
> (A) Performance counter stats for 'perf bench sched messaging -g 100 -l
>     1 -t'
>     # 20 sender and receiver threads per group
>     # 100 groups == 4000 threads run
> 

FWIW, our tests run with 1000 loops, not 1, and we don't use 100
groups for low cpu machines. We tend to test upto $((nproc * 4)).