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Message-ID: <7aa67fedb4b6dc9126bc59ee993fa18d0e472475.camel@linux.intel.com>
Subject: Re: [sched/fair]  ddb3b1126f:  hackbench.throughput -25.9%
 regression
From:   Tim Chen <tim.c.chen@linux.intel.com>
To:     kernel test robot <oliver.sang@intel.com>
Cc:     0day robot <lkp@intel.com>, Chen Yu <yu.c.chen@intel.com>,
        Walter Mack <walter.mack@intel.com>,
        LKML <linux-kernel@vger.kernel.org>, lkp@lists.01.org,
        ying.huang@intel.com, feng.tang@intel.com,
        zhengjun.xing@linux.intel.com, fengwei.yin@intel.com,
        Peter Zijlstra <peterz@infradead.org>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Ingo Molnar <mingo@elte.hu>,
        Juri Lelli <juri.lelli@redhat.com>,
        Mel Gorman <mgorman@suse.de>, aubrey.li@linux.intel.com
Date:   Wed, 30 Mar 2022 16:48:05 -0700
In-Reply-To: <20220330094632.GB6999@xsang-OptiPlex-9020>
References: <20220330094632.GB6999@xsang-OptiPlex-9020>
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On Wed, 2022-03-30 at 17:46 +0800, kernel test robot wrote:
> 
> Greeting,
> 
> FYI, we noticed a -25.9% regression of hackbench.throughput due to commit:
> 

Will try to check the regression seen.

Thanks.

Tim

> 
> 
> commit: 
>   d9ad181b93 ("sched/fair: Don't rely on ->exec_start for migration")
>   ddb3b1126f ("sched/fair: Simple runqueue order on migrate")
> 
> d9ad181b93f83b36 ddb3b1126fe93e8d6e059600488 
> ---------------- --------------------------- 
>          %stddev     %change         %stddev
>              \          |                \  
>      92566           -25.9%      68598 ±  2%  hackbench.throughput
>      85.50           +40.8%     120.35 ±  2%  hackbench.time.elapsed_time
>      85.50           +40.8%     120.35 ±  2%  hackbench.time.elapsed_time.max
>    9674391 ±  2%    +466.2%   54780205 ±  2%  hackbench.time.involuntary_context_switches
>       1240           +42.6%       1768 ±  3%  hackbench.time.system_time
>      89.58           +20.4%     107.85        hackbench.time.user_time
>   36626407          +270.2%  1.356e+08 ±  2%  hackbench.time.voluntary_context_switches
>    2500490 ±  3%     +78.2%    4456808 ±  3%  cpuidle..usage
>     118.45 ±  2%     +29.2%     153.02 ±  2%  uptime.boot
>