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?
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