Bugfixes:

• Fix InFlightTxCount become negative during split/merge
• Allow compatibility between non-stable versions of different applications
• Various stability improvements (segfault, handle balancer and boot queue events in StateInit, data race when reporting issue counters, memory leak in TRopeArena)
• CPU overutilization in case of numerous topic consumers
• Fix import multiple converted csv columns
• Fix mem table merge when writing over committed deltas in tablets
• Check errors during read_table_scan and export
• Throttle datashard log messages

Features:

• Enable ANSI settings for generic query
• DML logging
• Request unit trailing header for ScanQuery/ScanYql sctipts
• Grpc KV api
• Change default metering mode of topics to request units
• Pqv0 support on server side
• Allow to maintain unavailable nodes in tablets checker
• Allow to reboot unavailable node
• Add Lazy Histogram for grpc request