https://github.com/timescale/timescaledb/releases

Highlighted features in TimescaleDB v2.21.0

• The attach & detach chunks feature allows manually adding or removing chunks from a hypertable with uncompressed chunks, similar to PostgreSQL’s partition management.
• Continued improvement of backfilling into the columnstore, achieving up to 2.5x speedup for constrained tables, by introducing caching logic that boosts throughput for writes to compressed chunks, bringing INSERT performance close to that of uncompressed chunks.
• Optimized DELETE operations on the columstore through batch-level deletions of non-segmentby keys in the filter condition, greatly improving performance to up to 42x faster in some cases, as well as reducing bloat, and lowering resource usage.
• The heavy lock taken in Continuous Aggregate refresh was relaxed, enabling concurrent refreshes for non-overlapping ranges and eliminating the need for complex customer workarounds.
• [tech preview] Direct Compress is an innovative TimescaleDB feature that improves high-volume data ingestion by compressing data in memory and writing it directly to disk, reducing I/O overhead, eliminating dependency on background compression jobs, and significantly boosting insert performance.

Sunsetting of the hypercore access method
We made the decision to deprecate hypercore access method (TAM) with the 2.21.0 release. It was an experiment, which did not show the signals we hoped for and will be sunsetted in TimescaleDB 2.22.0, scheduled for September 2025. Upgrading to 2.22.0 and higher will be blocked if TAM is still in use. Since TAM’s inception in 2.18.0, we learned that btrees were not the right architecture. The recent advancements in the columnstore—such as more performant backfilling, SkipScan, adding check constraints, and faster point queries—put the columnstore close to or on par with TAM without the storage from the additional index. We apologize for the inconvenience this action potentially causes and are here to assist you during the migration process.