Horton
Menu

Re: Adding REPACK [concurrently]

Alvaro Herrera <alvherre@alvh.no-ip.org>

View thread
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: Mihail Nikalayeu <mihailnikalayeu@gmail.com>, Antonin Houska <ah@cybertec.at>, 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: 2026-04-07T12:33:50Z
Lists: pgsql-hackers 
On 2026-Apr-07, Amit Kapila wrote:

> I have a question based on 0001's commit message: "This patch adds a
> new option to logical replication output plugin, to declare that it
> does not use shared catalogs (i.e. catalogs that can be changed by
> transactions running in other databases in the cluster).". In which
> cases, currently plugin needs to access multi-database transactions or
> transactions that need to access shared catalogs and on what basis a
> plugin can decide that the changes it requires won't need any such
> access.

I don't think any plugin needs "multi-database" access as such, but
needing access to shared catalogs is likely normal.  Repack knows it
won't access any shared catalogs, so it can set the flag at ease.

There's a cross-check added in the commit that tests for access to
shared catalogs if the flag is set to false.  I guess you could set it
to false and see what breaks :-)

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.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