RE: Adding REPACK [concurrently]

Hayato Kuroda (Fujitsu) <kuroda.hayato@fujitsu.com>

From: "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>
To: 'Alvaro Herrera' <alvherre@alvh.no-ip.org>, Antonin Houska <ah@cybertec.at>
Cc: Srinath Reddy Sadipiralla <srinath2133@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>, Mihail Nikalayeu <mihailnikalayeu@gmail.com>, Matthias van de Meent <boekewurm+postgres@gmail.com>, Pg Hackers <pgsql-hackers@lists.postgresql.org>, Robert Treat <rob@xzilla.net>
Date: 2026-04-04T06:20:35Z
Lists: pgsql-hackers
Dear Álvaro,

While testing REPACK CONCURRENTLY command with xid_wraparound module, noticed that
wraparound-autovac worker was terminated with an error like below.

``
ERROR:  could not wait for concurrent REPACK
DETAIL:  Process 41512 waits for REPACK running on process 41027
CONTEXT:  waiting for ShareUpdateExclusiveLock on relation 16384 of database 5
        automatic vacuum of table "postgres.public.test"
```

The behavior is different from other commands, like LOCK and maybe normal REPACK.
In these cases the autovac worker would wait till the command fails.

Is it an intentional behavior? If so, what is the advantage that we terminate the
failsafe vacuum?

Best regards,
Hayato Kuroda
FUJITSU LIMITED

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Allow old WAL recycling during REPACK CONCURRENTLY

  2. Advance restart_lsn more eagerly in LogicalConfirmReceivedLocation

  3. Remove unnecessary signal handler change

  4. Improve REPACK (CONCURRENTLY) error messages some more

  5. Revert "Allow logical replication snapshots to be database-specific"

  6. Move REPACK (CONCURRENTLY) test out of stock regression tests

  7. REPACK: do not require REPLICATION or LOGIN

  8. Add missing initialization

  9. Simplify declaration of memcpy target

  10. Reserve replication slots specifically for REPACK

  11. doc: Add an example of REPACK (CONCURRENTLY)

  12. Allow logical replication snapshots to be database-specific

  13. Avoid different-size pointer-to-integer cast

  14. Fix valgrind failure

  15. Add CONCURRENTLY option to REPACK

  16. Rename cluster.c to repack.c (and corresponding .h)

  17. Allow index_create to suppress index_build progress reporting

  18. Make index_concurrently_create_copy more general

  19. Document the 'command' column of pg_stat_progress_repack

  20. Introduce the REPACK command

  21. Toggle logical decoding dynamically based on logical slot presence.

  22. Split vacuumdb to create vacuuming.c/h

  23. Remove ReorderBufferTupleBuf structure.

  24. Revert changes to CONCURRENTLY that "sped up" Xmin advance

  25. VACUUM: ignore indexing operations with CONCURRENTLY