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Date:   Wed, 15 Jan 2020 11:48:29 -0500
From:   "Theodore Y. Ts'o" <tytso@mit.edu>
To:     Ritesh Harjani <riteshh@linux.ibm.com>
Cc:     Jan Kara <jack@suse.cz>,
        Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>,
        Ext4 Developers List <linux-ext4@vger.kernel.org>,
        joseph.qi@linux.alibaba.com, Liu Bo <bo.liu@linux.alibaba.com>
Subject: Re: Discussion: is it time to remove dioread_nolock?
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 <20200114233054.890D7A4040@d06av23.portsmouth.uk.ibm.com>
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On Wed, Jan 15, 2020 at 05:00:53AM +0530, Ritesh Harjani wrote:
> 
> I too collected some performance numbers on my x86 box with
> --direct=1, bs=4K/1M & ioengine=libaio, with default opt v/s dioread_nolock
> opt on latest ext4 git tree.
> 
> I found the delta to be within +/- 6% in all of the runs which includes, seq
> read, mixed rw & mixed randrw.

Thanks for taking the performance measurements!

Are you able to release more detail of what the deltas were for those
tests?  And how stable were those results across repeated runs?

Thanks,

					- Ted