From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48466) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Vobvx-00058f-Jm for qemu-devel@nongnu.org; Thu, 05 Dec 2013 11:37:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Vobvr-0004yl-35 for qemu-devel@nongnu.org; Thu, 05 Dec 2013 11:37:49 -0500 Received: from nodalink.pck.nerim.net ([62.212.105.220]:44831 helo=paradis.irqsave.net) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Vobvq-0004ya-PP for qemu-devel@nongnu.org; Thu, 05 Dec 2013 11:37:43 -0500 Date: Thu, 5 Dec 2013 17:37:36 +0100 From: =?iso-8859-1?Q?Beno=EEt?= Canet Message-ID: <20131205163735.GG2892@irqsave.net> 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> <52A094CA.7050106@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <52A094CA.7050106@redhat.com> Content-Transfer-Encoding: quoted-printable 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: Eric Blake Cc: =?iso-8859-1?Q?Beno=EEt?= Canet , kwolf@redhat.com, famz@redhat.com, jcody@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com, stefanha@redhat.com Le Thursday 05 Dec 2013 =E0 07:59:22 (-0700), Eric Blake a =E9crit : > On 12/05/2013 07:43 AM, Beno=EEt Canet wrote: >=20 > >> 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-= only > >> interfaces - and making management responsible to track all named no= des > >> 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 suffici= ent 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= nodes. >=20 > 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. I will start by implementing the named nodes name list first. Don't worry for the other solution: my customer want crypto filters and m= ulti BlockDriver state throttling as a filter so I will continue to enable fil= ter in a progressive way. Best regards Beno=EEt >=20 > --=20 > Eric Blake eblake redhat com +1-919-301-3266 > Libvirt virtualization library http://libvirt.org >=20