From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57492) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YDWSY-0005Dd-DI for qemu-devel@nongnu.org; Tue, 20 Jan 2015 05:54:59 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YDWST-0000dA-Dr for qemu-devel@nongnu.org; Tue, 20 Jan 2015 05:54:58 -0500 Received: from cantor2.suse.de ([195.135.220.15]:38103 helo=mx2.suse.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YDWST-0000cx-6t for qemu-devel@nongnu.org; Tue, 20 Jan 2015 05:54:53 -0500 Message-ID: <54BE33FA.1000500@suse.de> Date: Tue, 20 Jan 2015 11:54:50 +0100 From: Alexander Graf MIME-Version: 1.0 References: <1419604968-87437-1-git-send-email-agraf@suse.de> <20150120103112.GI31174@grmbl.mre> In-Reply-To: <20150120103112.GI31174@grmbl.mre> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v3 0/5] Migration Deciphering aid List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Amit Shah Cc: pbonzini@redhat.com, quintela@redhat.com, qemu-devel@nongnu.org, afaerber@suse.de On 20.01.15 11:31, Amit Shah wrote: > On (Fri) 26 Dec 2014 [15:42:43], Alexander Graf wrote: >> Migration is a black hole to most people. One of the biggest reasons for >> this is that its protocol is a secret, undocumented sauce of code rolling >> around random parts of the QEMU code base. >> >> But what if we simply exposed the description of how the format looks like >> alongside the actual migration stream? This is what this patch set does. >> >> It adds a new section that comes after the end of stream marker (so that it >> doesn't slow down migration) that contains a JSON description of the device >> state description. >> >> Along with this patch set also comes a python script that can read said JSON >> from a migration dump and decipher the device state and ram contents of the >> migration dump using it. >> >> With this, you can now fully examine all glorious details that go over the >> wire when virtual machine state gets dumped, such as during live migration. >> >> We discussed the approach taken here during KVM Forum 2013. Originally, my idea >> was to include a special device that contains the JSON data which can be enabled >> on demand. Anthony suggested however to just always include the description data >> after the end marker which I think is a great idea. >> >> Example decoded migration: http://csgraf.de/mig/mig.txt >> Example migration description: http://csgraf.de/mig/mig.desc.txt >> Presentation: https://www.youtube.com/watch?v=iq1x40Qsrew >> Slides: https://www.dropbox.com/s/otp2pk2n3g087zp/Live%20Migration.pdf > > Nice to finally see this! > > I guess you have a v4 coming soon? Yeah, I was just waiting on a bit more review :) Alex