Re: Adding REPACK [concurrently]

Mihail Nikalayeu <mihailnikalayeu@gmail.com>

From: Mihail Nikalayeu <mihailnikalayeu@gmail.com>
To: Andres Freund <andres@anarazel.de>
Cc: Antonin Houska <ah@cybertec.at>, Amit Kapila <amit.kapila16@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Srinath Reddy Sadipiralla <srinath2133@gmail.com>, Matthias van de Meent <boekewurm+postgres@gmail.com>, Pg Hackers <pgsql-hackers@lists.postgresql.org>, Robert Treat <rob@xzilla.net>
Date: 2026-04-12T14:58:31Z
Lists: pgsql-hackers
Hi!

On Sun, Apr 12, 2026 at 4:05 PM Andres Freund <andres@anarazel.de> wrote:
> I don't think that's as good.  The problem is that that way you're only
> detecting the deadlocks once they have materialized (i.e. once repack actually
> does the lock upgrade), rather than cancelling when we know that the problem
> starts.  Having sessions pointlessly blocked for many hours is bad.

O, I think I understand you now.
You propose to somehow mark SUEL as "going to become AEL, so, the
deadlock detector should treat it as such".
In that case LOCK TABLE should get some kind of "future deadlock detected".

Yep, that feels much better. I'll try to check that approach tomorrow.

Best regards,
Mikhail.



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