On Wed, 1 Jul 2026 at 07:24, Japin Li <japinli@hotmail.com> wrote:
>
> Thanks for working on this.
Thank you for testing it!
> While testing the v5 patch, I encountered a lock wait.
>
> 2026-07-01 14:18:43.603 CST [1486593] LOG: process 1486593 still waiting for AccessExclusiveLock on relation 16384
ofdatabase 5 after 1000.106 ms
> 2026-07-01 14:18:43.603 CST [1486593] DETAIL: Process holding the lock: 1486484. Wait queue: 1486593.
> 2026-07-01 14:18:43.603 CST [1486593] CONTEXT: waiting for AccessExclusiveLock on relation 16384 of database 5
> 2026-07-01 14:18:43.603 CST [1486593] STATEMENT: SELECT * FROM gtt_delete;
>
> Is this expected?
Ah yes, you're right. That's not good.
The root cause looks to be the same issue that Pavel reported -- the
ON COMMIT DELETE ROWS does a TRUNCATE when the transaction is
committed, which requires an AccessExclusiveLock. I think the patch
should reduce the lock level required for TRUNCATE on a global
temporary relation to RowExclusiveLock, like DELETE.
I'll try to post an update later this week.
Regards,
Dean
