From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45098) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YVhqq-0000ww-4z for qemu-devel@nongnu.org; Wed, 11 Mar 2015 10:43:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YVhql-00057q-3m for qemu-devel@nongnu.org; Wed, 11 Mar 2015 10:43:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59904) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YVhqk-00057e-TP for qemu-devel@nongnu.org; Wed, 11 Mar 2015 10:43:07 -0400 Message-ID: <55005477.7000006@redhat.com> Date: Wed, 11 Mar 2015 08:43:03 -0600 From: Eric Blake MIME-Version: 1.0 References: <1425338403-16138-1-git-send-email-jsnow@redhat.com> <1425338403-16138-2-git-send-email-jsnow@redhat.com> <20150311134341.GE10493@stefanha-thinkpad.redhat.com> <55004EE9.8010302@redhat.com> In-Reply-To: <55004EE9.8010302@redhat.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="dW9rxoRjvAvLdL6V4Q9FklBRBeAk9gNTb" Subject: Re: [Qemu-devel] [Qemu-block] [PATCH v2 01/17] docs: incremental backup documentation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: John Snow , Stefan Hajnoczi Cc: vladimir Sementsov-Ogievskiy , "famz >> Fam Zheng" , qemu-devel , "armbru >> Markus Armbruster" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --dW9rxoRjvAvLdL6V4Q9FklBRBeAk9gNTb Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 03/11/2015 08:19 AM, John Snow wrote: >=20 >=20 > On 03/11/2015 09:43 AM, Stefan Hajnoczi wrote: >> On Mon, Mar 02, 2015 at 06:19:47PM -0500, John Snow wrote: >>> +## Bitmap Modes >>> + >>> +* A Bitmap can be "enabled" (tracking writes, the default) or >>> "disabled" >>> +(read-only, I/O is ignored.) This state is currently only changed >>> internally >>> +for the purposes of migration, and otherwise remains enabled. >> >> From a QMP API perspective this information is not relevant. The >> documentation is clearer without the concept of enabled/disabled. >> >=20 > Hm ... I suppose; If you want all mention of this gone from user view, = I > should actually remove this status field from the query, too. It is > entirely possible to have a state where the bitmap is not frozen, but i= t > is disabled (migration, perhaps others in the future?) so I left the > status visible to the user for now. >=20 > libvirt et al could likely rely on the migration status to know not to > manipulate bitmaps, but having that status information directly in the > bitmap didn't bother me. With a back-compat perspective, it's easier to hide the field now and add it later if we discover that it would have been useful to expose, than it is to expose it now and then have to support it forever even though no one uses it. I'm not yet sure if libvirt can make use of knowing whether a bitmap is frozen/disabled. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --dW9rxoRjvAvLdL6V4Q9FklBRBeAk9gNTb Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJVAFR3AAoJEKeha0olJ0NqCo8H/jBpGC3XHDQ6oEMBpur9w4E/ qbhoPEo3MseX9PQay8FToSd0+uD9CihEIi29x52O3yZ4jhCP+GSOv6fbhvzPf549 6DcQuk5QWDwH+l+6AtAxi85T5uDBQqE+jwlgsDloCP5j/9cOav0yXiKPwxB+Z3qO gsRJfmOzWkd06oa1NLNWwE+jC29NFOdkM0s3HON/uCd1CnXBxTwpb6/SM1W2ZCVf 6i5DQMz8R/LcS+MWjWARN4Or9YvL9t/unNGQzoVwEKQIDpUIfyvtsWIO4qazRlZL U0v5ToqSTJ0LpyYwJANACO6M/ZPk4zJjWsXNvHyqUo+uG49u4FCVH0NAPglVRP4= =Cn+T -----END PGP SIGNATURE----- --dW9rxoRjvAvLdL6V4Q9FklBRBeAk9gNTb--