From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:34631) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tn76t-00060r-TY for qemu-devel@nongnu.org; Mon, 24 Dec 2012 07:26:25 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Tn76s-0001N9-SU for qemu-devel@nongnu.org; Mon, 24 Dec 2012 07:26:23 -0500 Received: from nodalink.pck.nerim.net ([62.212.105.220]:55172 helo=paradis.irqsave.net) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tn76s-0001MZ-Kx for qemu-devel@nongnu.org; Mon, 24 Dec 2012 07:26:22 -0500 Date: Mon, 24 Dec 2012 13:26:38 +0100 From: =?iso-8859-1?Q?Beno=EEt?= Canet Message-ID: <20121224122638.GB3441@irqsave.net> References: <1353935123-24199-1-git-send-email-benoit@irqsave.net> <20121212161428.GC3478@irqsave.net> <20121218134239.GB6697@stefanha-thinkpad.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20121218134239.GB6697@stefanha-thinkpad.redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [RFC V3 00/24] QCOW2 deduplication List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: =?iso-8859-1?Q?Beno=EEt?= Canet , kwolf@redhat.com, qemu-devel@nongnu.org > Yes, it's the same problem that copy-on-read has. We can serialize I/O > requests, if necessary, in order to prevent them racing with each other= . My current patchset have a big dedup_lock co mutex. I'll replace it with the overlapping request solution. > Where do you see an issue - do you think the refcount manipulations > you're doing for dedup might conflict with internal snapshots? Ok, Anyway it seems to pass the savevm tests. Beno=EEt