From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37867) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zbne3-0000kK-37 for qemu-devel@nongnu.org; Tue, 15 Sep 2015 06:39:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zbndz-0006E3-NG for qemu-devel@nongnu.org; Tue, 15 Sep 2015 06:39:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56595) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zbndz-0006Dw-IZ for qemu-devel@nongnu.org; Tue, 15 Sep 2015 06:39:23 -0400 Date: Tue, 15 Sep 2015 16:09:09 +0530 From: Amit Shah Message-ID: <20150915103909.GD10281@grmbl.mre> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] [PATCH RFC 0/3] Checkpoint-assisted migration proposal List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Bohdan Trach Cc: Bohdan Trach , thomas.knauth@googlemail.com, qemu-devel@nongnu.org, quintela@redhat.com Hi, On (Fri) 17 Apr 2015 [14:12:59], Bohdan Trach wrote: > From: Bohdan Trach > > This patchset contains a checkpoint-assisted migration feature as > proposed earlier on this list [1]. It allows reusing existing memory > snapshots of guests to speed up migration of VMs between physical > hosts. > > [1] https://lists.gnu.org/archive/html/qemu-devel/2015-04/msg01555.html Could you please include a file in the docs/ directory that documents how this works, so it's easier to comment on the general idea? >>From 'checkpointing', I was afraid this was going to use some checkpoint-restore framework, but instead it's a new checkpointing method that you're adding to qemu. Can you describe when checkpoints are taken, and what is checkpointed? How is it stored on the disk? I'm sure the patches have all the details, but it's easier to check the soundness of the idea if there's a high-level doc that explains this, and then we can discuss the finer points over patches. Overall, I think this approach can benefit some workloads, and since it's not affecting a lot of common code, we could look at adding it. Also, apologies for not getting to this earlier. Thanks, Amit