Hubert (depesz) Lubaczewski • 4/21/2026

Waiting for PostgreSQL 19 – Add CONCURRENTLY option to REPACK

This article discusses a new feature in PostgreSQL 19: the CONCURRENTLY option for the REPACK command. This option allows table repacking without acquiring an access-exclusive lock until the final swap, using a replication slot and a background worker for logical decoding to capture concurrent changes. The author tests this feature on a 19 GB table with 200 million rows, deleting 80% of rows and running concurrent inserts. The article also notes limitations like scarce replication slots, single-process restriction, and deadlock risks, which will be addressed in future commits.

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#postgresql #Logical Decoding #Concurrent Repack