From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35766) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z3MCE-0000lr-Rq for qemu-devel@nongnu.org; Fri, 12 Jun 2015 06:28:23 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z3MCB-0006bk-Mb for qemu-devel@nongnu.org; Fri, 12 Jun 2015 06:28:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48438) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z3MCB-0006bb-HG for qemu-devel@nongnu.org; Fri, 12 Jun 2015 06:28:19 -0400 Date: Fri, 12 Jun 2015 11:28:16 +0100 From: Stefan Hajnoczi Message-ID: <20150612102815.GC623@stefanha-thinkpad.redhat.com> References: <1433776886-27239-1-git-send-email-vsementsov@virtuozzo.com> <1433776886-27239-2-git-send-email-vsementsov@virtuozzo.com> <20150609170325.GI3181@stefanha-thinkpad.redhat.com> <5577F312.9040502@virtuozzo.com> <20150610132420.GD2430@stefanha-thinkpad.home> <557960AC.4080607@virtuozzo.com> <20150611130309.GD9425@stefanha-thinkpad.redhat.com> <5579B58B.6020408@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="jy6Sn24JjFx/iggw" Content-Disposition: inline In-Reply-To: <5579B58B.6020408@redhat.com> Subject: Re: [Qemu-devel] [PATCH 1/8] spec: add qcow2-dirty-bitmaps specification List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: John Snow Cc: kwolf@redhat.com, Vladimir Sementsov-Ogievskiy , Stefan Hajnoczi , qemu-devel@nongnu.org, Vladimir Sementsov-Ogievskiy , den@openvz.org, pbonzini@redhat.com --jy6Sn24JjFx/iggw Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jun 11, 2015 at 12:21:31PM -0400, John Snow wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA256 >=20 >=20 >=20 > On 06/11/2015 09:03 AM, Stefan Hajnoczi wrote: > > On Thu, Jun 11, 2015 at 01:19:24PM +0300, Vladimir > > Sementsov-Ogievskiy wrote: > >> On 10.06.2015 16:24, Stefan Hajnoczi wrote: > >>> On Wed, Jun 10, 2015 at 11:19:30AM +0300, Vladimir > >>> Sementsov-Ogievskiy wrote: > >>>> On 09.06.2015 20:03, Stefan Hajnoczi wrote: > >>>>> On Mon, Jun 08, 2015 at 06:21:19PM +0300, Vladimir > >>>>> Sementsov-Ogievskiy wrote: > >>>>>> @@ -166,6 +167,19 @@ the header extension data. Each > >>>>>> entry look like this: terminated if it has full length)=20 > >>>>>> +=3D=3D Dirty bitmaps =3D=3D + +Dirty bitmaps is an optional > >>>>>> header extension. It provides a possibility of +storing > >>>>>> dirty bitmaps in qcow2 image. The fields are: + + > >>>>>> 0 - 3: nb_dirty_bitmaps + Number of > >>>>>> dirty bitmaps contained in the image > >>>>> Is there a maximum? > >>>> hmm. any proposals for this? > >>> 65535 seems practical. > >>=20 > >> So, you suggest to reduce this field width to 2b? And additional > >> 2 bytes reserved field, to achieve 8b-alignment? > >=20 > > No, I would leave it 32-bit but impose a little (which can be s/little/limit/ > > increased later if necessary). That's how nb_snapshots works too. > >=20 >=20 > Doesn't the code already limit the number of bitmaps via +#define > QCOW_MAX_DIRTY_BITMAPS 65536, from patch 2? It needs to be in the specification. --jy6Sn24JjFx/iggw Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJVerQ/AAoJEJykq7OBq3PIZnQIAKiIuUEJSj+LXqjZuhtlFXB0 79OjX6E4fNNL/GUXsgLOWwcwcyxIcQxK+gEhNoixZJvzKR/bqzDviWau58s24JsU wKPhquKvRK5sWV0+4OdRfOCC5tjAn8DxTMsvR6D6ozuU3I5CexURAG5yQpyKzxgy 9C7lOjO3xTakiLpiwcDlS7C0xu0XEqaXD2gcoQvNE5M/in/xby2qdy3BiJLb9UWH Sxs710Zm/9ILRsEsEeMlSrmeS80OiyEX9HeACpLhniNMRxsQLr1iHYaolXuJE3Us 0G72qg1Rc5wIbbTfd5okFUQsQhxNjR8khqfsdQXIAzaP3MQ/Wbr7GuQ8WvZkjFM= =i+4N -----END PGP SIGNATURE----- --jy6Sn24JjFx/iggw--