From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:54820) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tiogg-0008Ji-M7 for qemu-devel@nongnu.org; Wed, 12 Dec 2012 10:57:36 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Tioga-00052q-9j for qemu-devel@nongnu.org; Wed, 12 Dec 2012 10:57:34 -0500 Received: from nodalink.pck.nerim.net ([62.212.105.220]:51639 helo=paradis.irqsave.net) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tioga-00052O-2C for qemu-devel@nongnu.org; Wed, 12 Dec 2012 10:57:28 -0500 Date: Wed, 12 Dec 2012 16:57:38 +0100 From: =?iso-8859-1?Q?Beno=EEt?= Canet Message-ID: <20121212155737.GA3478@irqsave.net> References: <1353935123-24199-1-git-send-email-benoit@irqsave.net> <1353935123-24199-2-git-send-email-benoit@irqsave.net> <20121211113234.GH796@stefanha-thinkpad.muc.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20121211113234.GH796@stefanha-thinkpad.muc.redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [RFC V3 01/24] qcow2: Add deduplication to the qcow2 specification. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: kwolf@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com > Can you foresee the need to use a different hash algorithm in the futur= e > and should we add a hash_algo enum field to the dedup QCOW2 header > extension? Yes I foresee the future use of faster hash function like SHA3 or Skein. I also think an alternate deduplication mechanism where lookups are done on disk in order to be able to deduplicate very large volume could be add= ed. What would be the cleanest way to store this in the header extension ? bitmaps or two char fields ? Beno=EEt