From mboxrd@z Thu Jan  1 00:00:00 1970
From: Phillip Susi <psusi@cfl.rr.com>
Subject: Propagating queue/rotational up the stack
Date: Thu, 6 May 2010 10:11:12 -0400
Message-ID: <4BE2CE00.9050302@cfl.rr.com>
Reply-To: device-mapper development <dm-devel@redhat.com>
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I am running my root fs on an lvm lv situated on a pv built on an SSD,
and have noticed that ureadahead is optimizing for rotational disks
instead of SSD.  This is because the dm-0 block device's
queue/rotational entry in sysfs reports 1 instead of 0.  It seems that
this should be set to match the value of the underlying pv.  Would this
be possible and if so, would it be very difficult?