From mboxrd@z Thu Jan  1 00:00:00 1970
From: Karel Zak <kzak@redhat.com>
Subject: MD and rotational attribute
Date: Mon, 20 Feb 2012 13:20:22 +0100
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To: Neil Brown <neilb@suse.de>
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Hi Neil,

I guess that something is wrong with MD. If you create a RAID on ssd
(or scsi_debug in my example) than MD device is reported as rotational.
Simple example:

 modprobe scsi_debug dev_size_mb=500
 fdisk /dev/sdb
 ...
 mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sdb{1,2}

 # cat /sys/block/sdb/queue/rotational
 0
 # cat /sys/block/md0/queue/rotational
 1

It seems like a bug.

    Karel

-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com