Hi, It’s 2024 and users are still facing issues due to misconfigured compaction when using default configuration.
I would like to start a conversation around improving compaction defaults in 5.1/trunk, so users trying out CQL transactions don’t need to worry about tuning compaction. A few suggestions: 1) Make LeveledCompactionStrategy default on cassandra.yaml, UCS default on cassandra_latest.yaml ? 2) Does TWCS work out of the box with repairs and hints? My understanding is that due to CASSANDRA-10496 this causes droppable tombstone issues when in combination with repair and hints (see more on this thread [1]). We should either fix this or mark TWCS experimental. 3) When STCS is used with deletions/TTL, tombstones accumulate in higher level stables when unchecked_tombstone_compaction is disabled (see CASSANDRA-6563). I propose having adding a new setting “auto” enabled by default that will have this set to true when STCS/TWCS is used. I believe addressing these points will improve user experience with Cassandra. I apologize in advance if these topics were discussed in recent threads. I would be happy to get pointers of related discussions on this topic. I will be happy to create JIRA if there’s agreement on addressing these items. Thanks, Paulo [1] - https://user.cassandra.apache.narkive.com/VQOacfnT/twcs-repair-create-new-buckets-with-old-data
