From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dallas Clement <dallas.a.clement@gmail.com>
Subject: Re: best base / worst case RAID 5,6 write speeds
Date: Wed, 16 Dec 2015 09:31:43 -0600
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To: John Stoffel <john@stoffel.org>
Cc: Mark Knecht <markknecht@gmail.com>, Phil Turmel <philip@turmel.org>, Linux-RAID <linux-raid@vger.kernel.org>
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Phil, the 16k chunk size has really given a boost to my RAID 5
sequential write performance measured with fio, bs=1408k.

This is what I was getting with a 128k chunk size:

iodepth=4 => 605 MB/s
iodepth=8 => 589 MB/s
iodepth=16 => 634 MB/s
iodepth=32 => 635 MB/s

But this is what I'm getting with a 16k chunk size:

iodepth=4 => 825 MB/s
iodepth=8 => 810 MB/s
iodepth=16 => 851 MB/s
iodepth=32 => 866 MB/s