From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Martin K. Petersen" <martin.petersen@oracle.com>
Subject: Re: RAID-10 keeps aborting
Date: Thu, 6 Jun 2013 19:19:37 -0700 (PDT)
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To: Joe Lawrence <joe.lawrence@stratus.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>, "H. Peter Anvin" <hpa@zytor.com>, Dan Williams <dan.j.williams@gmail.com>, linux-raid <linux-raid@vger.kernel.org>
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>>>>> "Joe" == Joe Lawrence <joe.lawrence@stratus.com> writes:

Joe> I'm looking at the changes in raid1.c and am confused as to why we
Joe> did this in the first place (commit c8dc9c6):

Joe>         if (mddev->queue)
Joe>                 blk_queue_max_write_same_sectors(mddev->queue, mddev-> chunk_sectors);

Joe> for RAID1, aren't chunk_sectors always going to be zero?  (At least
Joe> on my machine, /sys/block/md*/queue/write_same_max_bytes for all md
Joe> RAID1 devices are set to 0.)  This would have the effect of
Joe> rendering bdev_write_same() always false for these MD devices.

I'm guessing that's a copy and paste from my raid0 support. In the raid0
case I set it to prevent straddling discard/write same commands.

-- 
Martin K. Petersen	Oracle Linux Engineering