New features:
- Implement [client writeback cache](docs/config/client.en.md#client_enable_writeback)
- Add the third I/O mode: [O_DIRECT|O_SYNC](docs/config/osd.en.md#data_io) (good for Optane)
- Reduce load on etcd by splitting OSD lease and statistics reporting intervals:
[etcd_stats_interval](docs/config/osd.en.md#etcd_stats_interval) (default 30 sec)
- Make MON automatically filter OSDs by layout (block_size/immediate_commit/bitmap_granularity)
to prevent "refusing to start PGs of this pool" errors on misconfiguration
- Support running fio benchmarks on systems without io_uring
- Make QEMU driver compatible with QEMU 8.1
- Document usage of [vhost-user-blk](docs/usage/qemu.en.md#vhost-user-blk)
Bug fixes:
- Fix resizing disks in QEMU driver (for example, in Proxmox)
- Fix "unexpected result" in Proxmox driver by making CLI flush output on exit
- Remove unneeded block_size mismatch warnings on pools without matching PGs
- Fix possible segfault in vitastor-cli ls -l (usually with deleted pools)
- Fix QEMU driver compatibility with systems without io_uring
- Fix monitor eating 100% CPU when etcd is down (caused by infinite retries)
- Fix potential incorrect write processing with snapshots (not caught in tests
but could probably lead to client hangs)
- Fix buffer insertion in cluster_client (not caught in tests but could
probably lead to incorrect writes in rare cases)
- Fix rare OSD crash during sync operation processing
- Fix a reenterability issue in cluster_client not reproducible in QEMU/fio,
but reproducible with the currently developed K/V database implementation
- Fix deletion of the first modified object - OSDs could crash if you modified
the same object a lot of times, then deleted it, and then modified it again
- Fix the fio_sec_osd test tool
Vitaliy Filippov