Currently we have both multi-thread compression and multifd to optimize live migration in Qemu. Mulit-thread compression deals with the situation where network bandwith is limited but cpu resource adequate. Multifd instead aims to take full advantage of network bandwith. Moreover it supports both zlib and zstd compression on each channel.
In this patch series, we did some code refactoring on multi-thread compression live migration and bring zstd compression method support for it. Below is the test result of multi-thread compression live migration with different compress methods. Test result shows that zstd outperforms zlib by about 70%. Migration Configuration: Guest 8U 32G compress-threads 8 decompress-threads 2 compress-level 1 bandwidth-limit 100Mbps Test Result: +---------------------+--------------+-------------+ | compress method | zlib | zstd | +---------------------+--------------+-------------+ | total time (ms) | 75256 | 44187 | +---------------------+--------------+-------------+ | downtime(ms) | 128 | 81 | +---------------------+--------------+-------------+ | transferred ram(kB)| 1576866 | 736117 | +---------------------+--------------+-------------+ | throughput(mbps) | 172.06 | 137.16 | +---------------------+--------------+-------------+ | total ram(kB) | 33685952 | 33685952 | +---------------------+--------------+-------------+ Zeyu Jin (6): migration: Add multi-thread compress method migration: Refactoring multi-thread compress migration migration: Add multi-thread compress ops migration: Add zstd support in multi-thread compression migration: Add compress_level sanity check doc: Update multi-thread compression doc docs/multi-thread-compression.txt | 31 ++- hw/core/qdev-properties-system.c | 11 + include/hw/qdev-properties.h | 4 + migration/migration.c | 56 ++++- migration/migration.h | 1 + migration/qemu-file.c | 62 +---- migration/qemu-file.h | 4 +- migration/ram.c | 381 +++++++++++++++++++++++++----- monitor/hmp-cmds.c | 12 + qapi/migration.json | 26 +- 10 files changed, 465 insertions(+), 123 deletions(-) -- 2.27.0
