From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from agk.surrey.redhat.com (agk.surrey.redhat.com [172.16.10.74]) by pobox.surrey.redhat.com (8.12.11.20060308/8.12.11) with ESMTP id k9QIXvNn030973 for ; Thu, 26 Oct 2006 19:33:57 +0100 Received: from agk by agk.surrey.redhat.com with local (Exim 4.34) id 1GdA3B-0001ca-KG for linux-lvm@redhat.com; Thu, 26 Oct 2006 19:33:57 +0100 Date: Thu, 26 Oct 2006 19:33:57 +0100 From: Alasdair G Kergon Subject: Re: [linux-lvm] [RFC, 2nd try] Let udev play with snapshots Message-ID: <20061026183357.GC1319@agk.surrey.redhat.com> References: <20061011173421.GC4636@hasse.suse.de> <20061023134100.GB4729@hasse.suse.de> <20061024182158.GC29513@agk.surrey.redhat.com> Mime-Version: 1.0 Content-Disposition: inline In-Reply-To: <20061024182158.GC29513@agk.surrey.redhat.com> Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: LVM general discussion and development On Tue, Oct 24, 2006 at 07:21:58PM +0100, Alasdair G Kergon wrote: > As discussed on irc, let's try to optimise out the deactivate/activate. I've checked in an attempt to do this: it turns out that the current structure of the code allows the simplest approach (skipping the cow deactivate) to work regardless of whether or not options like --persistent or --permission are supplied. The 'snapshot' LV mapped device gets created with the correct properties for the snapshot, but pointing to the cow and it gets zeroed. Then the cow is activated in a new mapped device and the old one gets reused for the proper snapshot. Alasdair -- agk@redhat.com