From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hannes Reinecke <hare@suse.de>
Subject: Discard support for dm-snap
Date: Thu, 02 Sep 2010 10:05:54 +0200
Message-ID: <4C7F5AE2.9020908@suse.de>
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Hi all,

now that we've got discard support in the block layer, are there plans
to update dm-snap to actually implement discard?
Looks like a valid addendum here; we could be freeing up unused blocks
thus freeing up space.
Especially helpful when using dm-snap to create a sparse device;
cf
http://www.mjmwired.net/kernel/Documentation/device-mapper/zero.txt

Thoughts?

Cheers,

Hannes
-- =

Dr. Hannes Reinecke		      zSeries & Storage
hare@suse.de			      +49 911 74053 688
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg
GF: Markus Rex, HRB 16746 (AG N=FCrnberg)