Changelog for Oban Met v1.3

v1.3.0 — 2026-08-01

Enhancements

• [Recorder] Restore :compressed option to series table

  The larger metrics_series table is now compressed, while the smaller metrics_latest remains uncompressed because it stays small.

• [Recorder] Bound compaction with chunking

  Prevent overlapping compactions and use a dedicated ETS table for chunked compaction. The resulting peak memory usage is ~61x lower with a relevant sample of ~260k rows.

  Compaction	Time	Peak memory	Table before	Table after
  Unbounded	849.7 ms	258.5 MiB	147.1 MiB	143.6 MiB
  Bounded	806.2 ms	4.2 MiB	147.1 MiB	143.5 MiB

• [Recorder] Restrict metric handoff to the PG notifier

  Handoff passes entire recorded tables between nodes over pubsub. The handoff size can easily be larger than what Postgres can deliver, which the notifier blocks. Rather than silently failing, handoff is restricted to the PG notifier.

• [Recorder] Chunk recorded table handoffs with acking

  Recorder handoff copied the entire table in a single payload using tab2list and term_to_binary. That spiked memory on both the sender and receiver, using hundreds of MB of memory with larger tables.

  The sender now streams the table through ETS continuation, sending 5k rows per message awaiting an ack before the next batch. Only one chunk is in flight at a time.

  The result is a ~5x smaller overall peak process heap:

  	elapsed	peak process	wire
  legacy full table	645 ms	202.0 MiB	3.53 MiB
  chunked 5,000	965 ms	39.4 MiB	3.62 MiB
  round trip 5,000	1817 ms	34.8 MiB	3.62 MiB