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Date:   Mon, 12 Oct 2020 09:18:25 +0100
From:   Mel Gorman <mgorman@techsingularity.net>
To:     Xing Zhengjun <zhengjun.xing@linux.intel.com>
Cc:     kernel test robot <rong.a.chen@intel.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Maxim Levitsky <mlevitsk@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>, lkp@lists.01.org
Subject: Re: [LKP] [fs] b6509f6a8c: will-it-scale.per_thread_ops -12.6%
 regression
Message-ID: <20201012081825.GR3227@techsingularity.net>
References: <20200706012029.GZ3874@shao2-debian>
 <6b301f34-f8fe-c626-e5e5-9af5c257c5c3@linux.intel.com>
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On Mon, Oct 12, 2020 at 02:20:26PM +0800, Xing Zhengjun wrote:
> Hi Mel,
> 
>    It is a revert commit caused the regression, Do you have a plan to fix
> it? Thanks. I re-test it in v5.9-rc8, the regression still existed.
> 

The revert caused a *performance* regression but the original
performance gain caused a functional failure. The overall performance
should be unchanged. I have not revisited the topic since.

-- 
Mel Gorman
SUSE Labs