Re: [Qemu-devel] [PATCH v2 for 4.1 0/2] avoid lseek on block_status

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

ping

08.04.2019 19:26, Vladimir Sementsov-Ogievskiy wrote:
> Hi!
> 
> It's a continuation for
> "[PATCH] qcow2: avoid lseek on block_status if possible"
> https://lists.gnu.org/archive/html/qemu-devel/2019-01/msg06598.html
> 
> performance results for block-status on tmpfs [tests originally by Kevin,
> now they are in 01]:
> 
> ./tests/perf/block/qcow2/convert-blockstatus /ramdisk/x
> 
> after 01:
> 
> plain: 81.77
> forward: 82.61
> prealloc: 0.01
> 
> after 02:
> 
> plain: 0.12
> forward: 0.12
> prealloc: 0.01
> 
> v2:
>   01: new
>   02: [mostly by Kevin's comments]
>       - rewritten to go through new flag BDRV_BLOCK_RECURSE
>       - never retry detection if failed for first time
>       - rewrite detection to do less iterations and to be more simple
> 
>       iotests 102 behavior changed [and not sure about other two ones
>       in comparison with v1, but it seems it doesn't matter]
> 
>       also, patch subject changed, as now it's a generic change for
>       block layer
> 
> 
> Vladimir Sementsov-Ogievskiy (2):
>    tests/perf: Test lseek influence on qcow2 block-status
>    block: avoid recursive block_status call if possible
> 
>   block/qcow2.h                              |  4 ++
>   include/block/block.h                      |  8 ++-
>   block/io.c                                 |  9 ++-
>   block/qcow2-refcount.c                     | 32 ++++++++++
>   block/qcow2.c                              | 11 ++++
>   tests/perf/block/qcow2/convert-blockstatus | 71 ++++++++++++++++++++++
>   tests/qemu-iotests/102                     |  2 +-
>   tests/qemu-iotests/102.out                 |  3 +-
>   tests/qemu-iotests/141.out                 |  2 +-
>   tests/qemu-iotests/144.out                 |  2 +-
>   10 files changed, 138 insertions(+), 6 deletions(-)
>   create mode 100755 tests/perf/block/qcow2/convert-blockstatus
> 


-- 
Best regards,
Vladimir