Re: Adding REPACK [concurrently]

Hello Antonin and Alvaro,

10.04.2026 13:57, Antonin Houska wrote:
> Attached is a fix that works for me.
>
> Nevertheless, REPACK (CONCURRENTLY) in your test goes ahead only due to commit
> 0d3dba38c7, which will probably be reverted [1]. Then REPACK will wait for the
> transaction in the other database (db1) to complete before it can actually
> start.

Thank you for the fix!

I've stumbled upon one more issue with this feature:
CREATE TABLE t (i int PRIMARY KEY);
REPACK (CONCURRENTLY) t;

fails for me with sanitizers enabled and
min_dynamic_shared_memory = '1GB'
in postgresql.conf as below:
2026-04-12 13:23:02.000 UTC [2733633] LOG:  statement: REPACK (CONCURRENTLY) t;
repack.c:3373:15: runtime error: load of value 240, which is not a valid value for type '_Bool'
    #0 0x6441f7eba454 in start_repack_decoding_worker .../src/backend/commands/repack.c:3373
    #1 0x6441f7ebdaad in rebuild_relation .../src/backend/commands/repack.c:1010
    #2 0x6441f7ebe9a2 in cluster_rel .../src/backend/commands/repack.c:656
    #3 0x6441f7ebefea in process_single_relation .../src/backend/commands/repack.c:2359
    #4 0x6441f7ebf870 in ExecRepack .../src/backend/commands/repack.c:296
    #5 0x6441f886f20e in standard_ProcessUtility .../src/backend/tcop/utility.c:867
...

2026-04-12 13:23:03.620 UTC [2733620] LOG:  client backend (PID 2733633) was terminated by signal 6: Aborted
2026-04-12 13:23:03.620 UTC [2733620] DETAIL:  Failed process was running: REPACK (CONCURRENTLY) t;

Could you please have a look?

Best regards,
Alexander