From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50512) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VoaOs-0002W5-Jv for qemu-devel@nongnu.org; Thu, 05 Dec 2013 09:59:39 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VoaOn-00084g-Ct for qemu-devel@nongnu.org; Thu, 05 Dec 2013 09:59:34 -0500 Received: from mx1.redhat.com ([209.132.183.28]:25295) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VoaOn-00084S-0N for qemu-devel@nongnu.org; Thu, 05 Dec 2013 09:59:29 -0500 Message-ID: <52A094CA.7050106@redhat.com> Date: Thu, 05 Dec 2013 07:59:22 -0700 From: Eric Blake MIME-Version: 1.0 References: <1386077165-19577-1-git-send-email-benoit@irqsave.net> <1386077165-19577-4-git-send-email-benoit@irqsave.net> <529FBEDA.9050409@redhat.com> <20131205142416.GD2892@irqsave.net> <52A08FED.7020305@redhat.com> <20131205144336.GE2892@irqsave.net> In-Reply-To: <20131205144336.GE2892@irqsave.net> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="dQs4enFwN8it33hiRbOIXCB80Av9mhilN" Subject: Re: [Qemu-devel] [RFC V3 3/7] qapi: Add skeletton of command to query a drive bs graph. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?B?QmVub8OudCBDYW5ldA==?= Cc: kwolf@redhat.com, famz@redhat.com, jcody@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com, stefanha@redhat.com This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --dQs4enFwN8it33hiRbOIXCB80Av9mhilN Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 12/05/2013 07:43 AM, Beno=C3=AEt Canet wrote: >> There's one case where management might not know - if libvirtd gets >> restarted while in the middle of an operation that was attempting to >> create a named node, then on restart and reconnection to the monitor, >> libvirt would want to query to see if the node actually got created or= >> if the command needs to be attempted again. I'm not a fan of write-on= ly >> interfaces - and making management responsible to track all named node= s >> with no way to query if qemu actually agrees with the topology that >> management thinks it has commanded feels like a write-only interface. >=20 > Would a command returning info about a specific named node be sufficien= t for > libvirt checks ? > It's far less complex to implement than exposing the whole graph. > We could also provide a simple command to list the names of the named n= odes. Yes, both of those ideas are useful; it still means management must track the topology between the nodes, but it at least gives management enough control to know which set of nodes exist to confirm which operations have occurred. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --dQs4enFwN8it33hiRbOIXCB80Av9mhilN Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.15 (GNU/Linux) Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJSoJTKAAoJEKeha0olJ0NqkQYH/3URd3xmHd/AuGumySGiqjMr sj801aStg/q3kUizfSiRLDUZ8IA9VSekECibc7ymZZPjlw+AL490sFnAHlyuOZ4z uBMGmVVMgATDbPEyKaGTYxRvd09SQ83DEQnKD8zjK7cUCcCu5ePKg3U3utg1JnC2 OKHgIHTtsWRgOZlPYnkTN7vJRQSw1imXmRMQLVl/qGDhfvafAUTlqouG+fi6/3AA IzUHr3yi4YiBXn5dKYKfsW4xn8qfO2t1rS20ISAtVS4aHhZFd/Ngx10itw9AjQgt yBv5GLVD3AmGWZzI+WYOW6i3PH+wLQHuR3mWmUCXIwTAEPNCG/JQrDp20ss8oI4= =muQF -----END PGP SIGNATURE----- --dQs4enFwN8it33hiRbOIXCB80Av9mhilN--