Re: [Qemu-devel] [PATCH v4 0/27] write/create for Parallels images with reasonable performance

["Denis V. Lunev" <den@openvz.org>]

On 28/04/15 10:46, Denis V. Lunev wrote:
> This patchset provides an ability to create of/write to Parallels
> images and some testing of the new code. Readings and writings are
> optimized out and I expect the same or slightly better performance
> as qcow2.
>
> Changes from v4:
> - parallels format driver marked as bdrv_has_zero_init_1
> - added missed unlocks to parallels_co_readv/writev on error path, locking
>    is shortened and simplified
> - changed test number for created images
> - added check for bdrv_has_zero_init() and availability of bdrv_truncate()
>    in parallels_open() and proper error handling in alloc_cluster
> - some patch comments are improved
>
> Changes from v3:
> - fixed checkpatch warnings even in just moved code. I am tired of them
> - fixed contingency check in patch 18
>
> Changes from v2:
> - read performance is almost doubled (up to 360 Mb/sec), write performance
>    is improved by 15-20%
> - bat caching approach changed completely. bat_bitmap now contains the data
>    in on-disk format, which allows to use this data for metadata cache
> - incorrect close detection code is added (inuse field in the header)
> - very basic check consistency code added
>
> Changes from v1:
> - patches 13-19 added, which boosts performance from 800 KiB/sec to
>    near native performance
>
> Signed-off-by: Denis V. Lunev <den@openvz.org>
> CC: Roman Kagan <rkagan@parallels.com>
> CC: Kevin Wolf <kwolf@redhat.com>
> CC: Stefan Hajnoczi <stefanha@redhat.com>
>
ping