Re: Adding REPACK [concurrently] - Mailing list pgsql-hackers

Hi!

On Thu, Apr 9, 2026 at 10:43 AM Antonin Houska <ah@cybertec.at> wrote:
> This approach LGTM when it comes to concurrent DDLs. However, consider REPACK
> holding ShareUpdateExclusiveLock (SUEL) and VACUUM (w/o VACOPT_SKIP_LOCKED)
> waiting for the same lock. Once REPACK releases its SUEL, VACUUM gets it and
> processes the table, then REPACK finally gets AccessExclusiveLock (AEL) and
> finishes too.

> One more thing we may prevent from sneaking into that hole is a
> VACUUM. It will not break anything, but will be huge waste of time and
> resources.


I thought about that too, I think we may just add some kind of
CheckTableNotInUse in VACUUM after getting the SUEL.

Mikhail.