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Date:   Fri, 21 May 2021 12:42:16 -0400
From:   "Theodore Y. Ts'o" <tytso@mit.edu>
To:     Jan Kara <jack@suse.cz>
Cc:     Xing Zhengjun <zhengjun.xing@linux.intel.com>,
        kernel test robot <oliver.sang@intel.com>,
        LKML <linux-kernel@vger.kernel.org>, lkp@lists.01.org,
        lkp@intel.com
Subject: Re: [LKP] [ext4] 05c2c00f37: aim7.jobs-per-min -11.8% regression
Message-ID: <YKfi6Pv+qwduKxuT@mit.edu>
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 <20210521092730.GE18952@quack2.suse.cz>
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On Fri, May 21, 2021 at 11:27:30AM +0200, Jan Kara wrote:
> 
> OK, thanks for testing. So the orphan code is indeed the likely cause of
> this regression but I probably did not guess correctly what is the
> contention point there. Then I guess I need to reproduce and do more
> digging why the contention happens...

Hmm... what if we only recalculate the superblock checksum when we do
a commit, via the callback function from the jbd2 layer to file
system?

					- Ted