ping ping ping ping! On 11.03.2019 11:20, Denis Plotnikov wrote: > ping ping ping! > > On 04.03.2019 18:10, Denis Plotnikov wrote: >> ping! >> >> On 26.02.2019 16:15, Denis Plotnikov wrote: >>> zstd date compression algorithm shows better performance on data >>> compression. >>> It might be useful to employ the algorithm in VM migration to reduce CPU >>> usage. >>> A user will be able to choose between those algorithms, therefor >>> compress-type >>> migration parameter is added. >>> >>> Here are some results of performance comparison zstd vs gzip: >>> >>> host: i7-4790 8xCPU @ 3.60GHz, 16G RAM >>> migration to the same host >>> VM: 2xVCPU, 8G RAM total >>> 5G RAM used, memory populated with postgreqsl data >>> produced by pgbench performance benchmark >>> >>> >>> Threads: 1 compress – 1 decompress >>> >>> zstd provides slightly less compression ratio with almost the same >>> CPU usage but copes with RAM compression roghly 2 times faster >>> >>> compression type zlib | zstd >>> --------------------------------------------------------- >>> compression level 1 5 | 1 5 >>> compression ratio 6.92 7.05 | 6.69 6.89 >>> cpu idle, % 82 83 | 86 80 >>> time, sec 49 71 | 26 31 >>> time diff to zlib, sec -25 -41 >>> >>> >>> Threads: 8 compress – 2 decompress >>> >>> zstd provides the same migration time with less cpu consumption >>> >>> compression type none | gzip(zlib) | zstd >>> ------------------------------------------------------------------------------ >>> compression level - | 1 5 9 | 1 5 15 >>> compression ratio - | 6.94 6.99 7.14 | 6.64 6.89 >>> 6.93 >>> time, sec 154 | 22 23 27 | 23 23 25 >>> cpu idle, % 99 | 45 30 12 | 70 52 23 >>> cpu idle diff to zlib | | -25% -22% >>> -11% >>> >>> >>> Denis Plotnikov (3): >>> migration: rework compression code for adding more data compressors >>> hmp: add compress-type parameter to migration parameters >>> migration: add zstd compression >>> >>> configure | 26 ++++ >>> hmp.c | 8 ++ >>> migration/migration.c | 45 ++++++- >>> migration/migration.h | 1 + >>> migration/qemu-file.c | 39 ++---- >>> migration/qemu-file.h | 18 ++- >>> migration/ram.c | 291 ++++++++++++++++++++++++++++++++++-------- >>> qapi/migration.json | 26 +++- >>> 8 files changed, 369 insertions(+), 85 deletions(-) >>> >> >
-- Best, Denis