ScyllaDB Enterprise 2021.1.9

The ScyllaDB team announces ScyllaDB Enterprise 2021.1.9, a bug-fix production-ready ScyllaDB Enterprise patch release for ScyllaDB Enterprise 2021.1. ScyllaDB Enterprise customers are encouraged to upgrade to ScyllaDB Enterprise 2021.1.9 in coordination with the ScyllaDB support team.

ScyllaDB Enterprise 2021.1.9 brings focus on bug fixes, stabilization and tooling improvement. More below.

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A list of performance and stability improvements and bug fixes below, each with open source reference, is available:

  • Performance: Implement tombstone compaction (a.k.a. garbage collection) for ICS.
    Tombstone compaction is a logic in compaction strategies that will trigger compaction based on (expired) tombstone density of files, to prevent accumulation of tombstones over time. This does not require any configuration or options update by the user. For more information on ICS, see here.
  • Performance: When using Time Window Compaction Strategy (TWCS), ScyllaDB will now compact tombstones across buckets, so they can remove the deleted data. Note that using DELETE with TWCS is still not recommended. #9662
  • Performance: For some time now, ScyllaDB reshards (rearranges SSTables to contain data for one shard) on boot. This means we can stop considering multi-shard SSTables in compaction, as done here. This speeds up compaction a little. A similar change was done to cleanup compactions. #7748
  • Stability:SSTable reshape for Size-Tiered Compaction Strategy has been fixed. Reshape happens when the node starts up and finds its SSTables do not conform to the strategy invariants, or on import. It then compacts the data so the invariants are preserved, guaranteeing reasonable read amplification. A bug caused reshape to be ignored for this compaction strategy. #7774
  • Stability: Better repair memory usage tracking and oom protection #9817
  • Stability: Possible Division by zero in empty estimated_histogram #9531

24 Feb 2022