Re: Adding REPACK [concurrently]

Antonin Houska <ah@cybertec.at>

From: Antonin Houska <ah@cybertec.at>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, Mihail Nikalayeu <mihailnikalayeu@gmail.com>, 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: 2026-04-01T12:31:21Z
Lists: pgsql-hackers
Amit Kapila <amit.kapila16@gmail.com> wrote:

> On Wed, Apr 1, 2026 at 3:13 PM Antonin Houska <ah@cybertec.at> wrote:
> >

> > Nevertheless, I'm not sure it's a good idea for snapbuild.c to handle special
> > cases like REPACK. Instead, I'm thinking if snapbuild.c can safely ignore XIDs
> > of backends connected to databases other than the one we're decoding.
> >
> 
> What if such transactions have made changes in the global catalog?
> Even if that won't matter, I feel such a change would be quite
> fundamental to snapbuild machinery and changing at this point would be
> risky.

I had thought that catalog is usually needed only to retrieve the tuple
descriptor, but regression tests with some Assert() statements prove now that
shared catalogs can be accessed too. So that idea does not seem to be useful.

-- 
Antonin Houska
Web: https://www.cybertec-postgresql.com



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