From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=42370 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OHEkO-00068Z-10 for qemu-devel@nongnu.org; Wed, 26 May 2010 07:26:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OHEkM-00030U-57 for qemu-devel@nongnu.org; Wed, 26 May 2010 07:26:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39411) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OHEkL-0002zM-Ly for qemu-devel@nongnu.org; Wed, 26 May 2010 07:26:02 -0400 Date: Wed, 26 May 2010 11:33:46 +0100 From: "Daniel P. Berrange" Message-ID: <20100526103346.GK18547@redhat.com> References: <9b6575587d22a5c85ec536172810520ee3b945d5.1274796992.git.quintela@redhat.com> <4BFBE843.5070202@codemonkey.ws> <4BFBF36D.8070208@codemonkey.ws> <20100525162549.GQ31759@redhat.com> <4BFBFBCB.2070806@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: [Qemu-devel] Re: [PATCH 3/5] QMP: Introduce MIGRATION events Reply-To: "Daniel P. Berrange" List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Juan Quintela Cc: qemu-devel@nongnu.org On Tue, May 25, 2010 at 06:43:13PM +0200, Juan Quintela wrote: > Anthony Liguori wrote: > > On 05/25/2010 11:25 AM, Daniel P. Berrange wrote: > >> On Tue, May 25, 2010 at 06:04:17PM +0200, Juan Quintela wrote: > >> > >>> Anthony Liguori wrote: > > > I'm not sure why you would need a notification of when migration > > starts (since you know when you've started migration). > > But you don't know if the other end "knows" that it has also started. > > started is needed only in incoming part, because .... we don't have a > monitor to ask if migration has started. If we ever want to get closer to allowing multiple monitors, or allowing apps to issue QMP commands directly via libvirt, then we still need the 'migration started' event on the source, because something else can have issued the 'migrate' command without the mgmt app knowing. MIGRATED_STARTED+STOPPED really *is* needed if we're to make QMP cope with all possible use cases. If we rely on inferring it from STOP+RESUME events, it is going to exclude a significant set of use cases, and likely result in this being proposed all over again in 12 months time :-( Regards, Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://deltacloud.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|