From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53063) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YvRD2-0001Fu-W6 for qemu-devel@nongnu.org; Thu, 21 May 2015 10:12:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YvRCx-0006bG-Gz for qemu-devel@nongnu.org; Thu, 21 May 2015 10:12:28 -0400 Received: from relay.parallels.com ([195.214.232.42]:32918) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YvRCx-0006Zo-5f for qemu-devel@nongnu.org; Thu, 21 May 2015 10:12:23 -0400 Message-ID: <555DE2D7.2020200@parallels.com> Date: Thu, 21 May 2015 16:51:19 +0300 From: Vladimir Sementsov-Ogievskiy MIME-Version: 1.0 References: <1431531007-10269-1-git-send-email-vsementsov@parallels.com> In-Reply-To: <1431531007-10269-1-git-send-email-vsementsov@parallels.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v5 00/12] Dirty bitmaps migration List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, peter.maydell@linaro.org, quintela@redhat.com, dgilbert@redhat.com, stefanha@redhat.com, den@openvz.org, amit.shah@redhat.com, pbonzini@redhat.com, jsnow@redhat.com Hi all. Hmm. There is an interesting suggestion from Denis Lunev (in CC) about how to drop meta bitmaps and make things easer. method: > start migration disk and memory are migrated, but not dirty bitmaps. > stop vm create all necessary bitmaps in destination vm (empty, but with same names and granularities and enabled flag) > start destination vm empty bitmaps are tracking now > start migrating dirty bitmaps. merge them to corresponding bitmaps in destination while bitmaps are migrating, they should be in some kind of 'inconsistent' state. so, we can't start backup or other migration while bitmaps are migrating, but vm is already _running_ on destination. what do you think about it? On 13.05.2015 18:29, Vladimir Sementsov-Ogievskiy wrote: > These patches provide dirty bitmap migration feature. Only named dirty > bitmaps are to be migrated. Migration may be enabled using migration > capabilities. > > v5: > - rebase on master > - drop [PATCH RFC v4 10/13] iotests: add event_wait to VM class > - remove rfc, as incremental backup series by John Snow are in > upstream > > > v4 significant changes: > 0001: tiny bugfix: out[i] -> out[i-start], same for 'in' > 0007: set chunk size to 1kb, disable live iteration for > migrating data < 1mb size. > > tests: only one with md5 sum is here. used function event_wait > by John Snow. (I hope, you don't mind me just adding this > function with your 'Signed-off-by') > > rfc: This patch set is based on v13 of > "block: incremental backup series" by John Snow, which are > not pushed yet. > > v3: > based on v13 of "block: incremental backup series" by John Snow. > > changes from v2: > removed patch for adding dirty parameter (migration capablities used > instead). > > 0001: printf's dropped, qapi used > 0002: part0 -> zeroes > 0003: part0 -> zeroes > 0005: dirty_dirty -> meta > add comments about meta bitmap > > 0006: the format is changed, nodes used instead of devices. > > other patches are new. > > rfc: there are two tests. They are the same but using different > interfaces: md5 checksum of the bitmap last layer in query-block or > separate query-block-dirty-bitmap with dirty bitmap regions. > The second form is more appropriate for debugging, the first is more > appropriate for simple regression control. Which should go to > upstream? > > v2: > 1. bug-fixes, that are already in upstream, and renaming of function > bdrv_reset_dirty_bitmap (which is already in Snow's series) are > dropped > 2. bitmap store/restore: the concept renamed to serialization, added > function hbitmap_deserialize_part0, to not transfer zero blocks > 3. migration dirty parameter: added description comment > 4. Other patches are new. > > v2.rfc: > Actually, in this version of the series I'm trying not use > migration/block.c at all. Instead a separate migration unit is added > in the new file migration/dirty-bitmap.c. Now bitmaps are migrated > like blocks in block migration, they have their "dirty-dirty" bitmaps, > for tracking set/unset changes during migration. > > The advantages are: > - no complications of migration/block.c > - separate dirty-dirty bitmaps provide handling of "unset's" > - more effective meta-data/data ratio - no tiny bitmap-blocks. > > > > v1: > These patches provide dirty bitmap migration feature. Only named dirty > bitmaps are to be migrated. Migration is made as a part of block > migration in block-migration.c. > > Dirty bitmap migration may be enabled by "dirty" parameter for qmp migrate > command. If "blk" and "inc" parameters are false when "dirty" is true > block migration is actually skipped: no allocatoions, no bdrv_read's, > no bdrv_write's, only bitmaps are migrated. > > The patch set includes two my previous bug fixes, which are necessary > for it. The patch set is based on Incremental backup series by John > Snow. > Vladimir Sementsov-Ogievskiy (12): > hbitmap: serialization > block: BdrvDirtyBitmap serialization interface > block: tiny refactoring: minimize hbitmap_(set/reset) usage > block: add meta bitmaps > block: add bdrv_next_dirty_bitmap() > qapi: add dirty-bitmaps migration capability > migration: add migration/block-dirty-bitmap.c > iotests: maintain several vms in test > iotests: add add_incoming_migration to VM class > qapi: add md5 checksum of last dirty bitmap level to query-block > iotests: add dirty bitmap migration test > migration/qemu-file: make functions qemu_(get/put)_string public > > block.c | 98 +++++- > include/block/block.h | 22 ++ > include/migration/block.h | 1 + > include/migration/migration.h | 1 + > include/migration/qemu-file.h | 17 + > include/qemu/hbitmap.h | 67 ++++ > migration/Makefile.objs | 2 +- > migration/block-dirty-bitmap.c | 693 +++++++++++++++++++++++++++++++++++++++++ > migration/migration.c | 9 + > migration/qemu-file.c | 18 ++ > qapi-schema.json | 4 +- > qapi/block-core.json | 4 +- > tests/qemu-iotests/117 | 84 +++++ > tests/qemu-iotests/117.out | 5 + > tests/qemu-iotests/group | 1 + > tests/qemu-iotests/iotests.py | 14 +- > util/hbitmap.c | 106 +++++++ > vl.c | 1 + > 18 files changed, 1137 insertions(+), 10 deletions(-) > create mode 100644 migration/block-dirty-bitmap.c > create mode 100755 tests/qemu-iotests/117 > create mode 100644 tests/qemu-iotests/117.out > -- Best regards, Vladimir