Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> writes: > 04.03.2020 16:35, Denis Plotnikov wrote: >> zstd significantly reduces cluster compression time. >> It provides better compression performance maintaining >> the same level of the compression ratio in comparison with >> zlib, which, at the moment, is the only compression >> method available. >> >> The performance test results: >> Test compresses and decompresses qemu qcow2 image with just >> installed rhel-7.6 guest. >> Image cluster size: 64K. Image on disk size: 2.2G >> >> The test was conducted with brd disk to reduce the influence >> of disk subsystem to the test results. >> The results is given in seconds. >> >> compress cmd: >> time ./qemu-img convert -O qcow2 -c -o compression_type=[zlib|zstd] >> src.img [zlib|zstd]_compressed.img >> decompress cmd >> time ./qemu-img convert -O qcow2 >> [zlib|zstd]_compressed.img uncompressed.img >> >> compression decompression >> zlib zstd zlib zstd >> ------------------------------------------------------------ >> real 65.5 16.3 (-75 %) 1.9 1.6 (-16 %) >> user 65.0 15.8 5.3 2.5 >> sys 3.3 0.2 2.0 2.0 >> >> Both ZLIB and ZSTD gave the same compression ratio: 1.57 >> compressed image size in both cases: 1.4G >> >> Signed-off-by: Denis Plotnikov <dplotni...@virtuozzo.com> >> QAPI part: >> Acked-by: Markus Armbruster <arm...@redhat.com> >> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> > > Looks a bit like I've reviewed only QAPI part, when actually my r-b is for > full patch... > > May be > > Acked-by: Markus Armbruster <arm...@redhat.com> > [QAPI part] > Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
No objection. We habitually use Acked-by: Markus Armbruster <arm...@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> I'm okay with that, too.
