From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41202) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y9Lgn-0003oa-MY for qemu-devel@nongnu.org; Thu, 08 Jan 2015 17:36:26 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Y9Lgl-0001WI-1S for qemu-devel@nongnu.org; Thu, 08 Jan 2015 17:36:25 -0500 Received: from mail-we0-x22b.google.com ([2a00:1450:400c:c03::22b]:47357) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y9Lgk-0001W0-QS for qemu-devel@nongnu.org; Thu, 08 Jan 2015 17:36:22 -0500 Received: by mail-we0-f171.google.com with SMTP id u56so5005205wes.2 for ; Thu, 08 Jan 2015 14:36:22 -0800 (PST) Sender: Paolo Bonzini Message-ID: <54AF0662.7050303@redhat.com> Date: Thu, 08 Jan 2015 23:36:18 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <1418307457-25996-1-git-send-email-vsementsov@parallels.com> <1418307457-25996-10-git-send-email-vsementsov@parallels.com> In-Reply-To: <1418307457-25996-10-git-send-email-vsementsov@parallels.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH 9/9] block-migration: add named dirty bitmaps migration List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org Cc: kwolf@redhat.com, den@openvz.org, jsnow@redhat.com, stefanha@redhat.com On 11/12/2014 15:17, Vladimir Sementsov-Ogievskiy wrote: > Just migrate parts of dirty bitmaps, corresponding to the block being > migrated. Also, skip block migration if it is disabled (blk parameter > of migrate command is false). > > Skipping shared sectors: bitmaps are migrated independently of this, > just send blk without block data. I think dirty bitmaps should be migrated separately from the block migration. It makes a lot of sense to migrate them even if you are not using block migration. Compared to new flags, the availability of migration capabilities can be queried via query-migrate-capabilities before actually invoking the migration. So they are preferred, and you should add a migration capability instead of a new argument. The bitmaps are transmitted many times in their entirety, but only the last copy actually means something. The others are lost. This means you should use the non-live interface (register_savevm). This will simplify the code a lot. Paolo