From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heinz Mauelshagen Subject: Re: [PATCH] dm-thinp: new device mapper target to thin provision storage Date: Wed, 29 Sep 2010 13:25:12 +0200 Message-ID: <1285759512.23010.1.camel@o> References: <1285706977.22966.20.camel@o> <4CA261C5.7070005@cfl.rr.com> Reply-To: heinzm@redhat.com, device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4CA261C5.7070005@cfl.rr.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: device-mapper development Cc: agk@redhat.com List-Id: dm-devel.ids On Tue, 2010-09-28 at 17:44 -0400, Phillip Susi wrote: > On 9/28/2010 4:49 PM, Heinz Mauelshagen wrote: > > > > These are 2 new device mapper targets "thinp" and "thinp-dev" > > implemented in one module, which allow for thin provisioning of storage > > on a single host from a storage pool to an arbitrary amount of devices. > > How is this different than snapshotting a zero target? Like Hanness mentioned: you can free space. > > > +Create an ext4 filesystem on the thin provisioned device: > > +mkfs -t ext4 /dev/mapper/thinp1 > > FYI, that tends to spend a lot of time writing hundreds of mb of zeros > to the inode tables, allocating chunks from the backing store. You > might want to add -E lazy_itable_init to stop that. Thanks for the hint, I waned to have load on the thin provisioned devices so far for testing but will have a look at the reduced allocations with this option. > > -- > dm-devel mailing list > dm-devel@redhat.com > https://www.redhat.com/mailman/listinfo/dm-devel