Re: Adding REPACK [concurrently]

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

From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Srinath Reddy Sadipiralla <srinath2133@gmail.com>
Cc: Antonin Houska <ah@cybertec.at>, 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: 2026-04-04T13:55:48Z
Lists: pgsql-hackers
On 2026-Apr-04, Srinath Reddy Sadipiralla wrote:

> yes indeed , TotalMaxReplicationSlots was the culprit , as the window
> after getting repack worked was forked , i think this was set back to 0.
> Thanks for fixing this with "repack" flag , initially i thought why can't we
> go with a macro
> #define TotalMaxReplicationSlots (max_replication_slots +
> max_repack_replication_slots)
> but i thought maybe in future we might need this "repack" flag to add
> more slot requirements.

Yeah, the other option would have been to add the variable to
restore_backend_variables() so that it's restored after the fork+exec,
but that didn't seem better.

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/
"Niemand ist mehr Sklave, als der sich für frei hält, ohne es zu sein."
       Nadie está tan esclavizado como el que se cree libre no siéndolo
                                           (Johann Wolfgang von Goethe)



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