On Mon, Nov 14, 2011 at 01:05:29AM +0000, Ben Hutchings wrote: > On Thu, 2011-11-10 at 11:59 -0800, Josh Triplett wrote: > > Source: linux-2.6 > > Version: 3.1.0-1~experimental.1 > > Severity: normal > > > > I use dm-crypt on my system, and I have an SSD. The underlying disk > > device, sda, has rotational=0: > > > > ~$ cat /sys/block/sda/queue/rotational > > 0 > > > > However, the device-mapper devices have rotational=1: > > > > ~$ head /sys/block/dm-*/queue/rotational > > ==> /sys/block/dm-0/queue/rotational <== > > 1 > > > > ==> /sys/block/dm-1/queue/rotational <== > > 1 > > > > ==> /sys/block/dm-2/queue/rotational <== > > 1 > > > > The device-mapper devices should inherit the setting for "rotational" > > from their underlying devices. > > I'm not sure that's true. Since their queues should feed into the > queues for the underlying devices, it may be that they shouldn't > themselves be scheduled as if they are rotating media. OK, I suppose I don't actually care what rotational shows for a device-mapper device backed by rotating media. The case I care about: when the underlying media has rotational=0, the dm device definitely shouldn't have rotational=1. - Josh Triplett -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
