Re: The same again with 16.9 : was Re: PostgreSQL 16.6 , query stuck with STAT Ssl, wait_event_type : IPC , wait_event : ParallelFinish

On Fri, 2025-08-22 at 09:16 +0100, Achilleas Mantzios wrote:
> we had the same problem today again.
>
> postgres(at)[local]/dynacom=# select * from pg_stat_activity where application_name~*'dbmirr';
>  -[ RECORD 1 ]----+-----------------------------------------------------------------------------------------------
> [...]
>  pid              | 1821681
> [...]
>  wait_event_type  | IPC
>  wait_event       | ParallelFinish
>  state            | active
>
> postgres(at)smadb:~$ ps -u -p 1821681
>  USER         PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
>  postgres 1821681  0.5  4.8 37111844 3177260 ?    Ssl  03:58   2:25 postgres: postgres dynacom 10.9.0.10(45051) SELECT

Did you check whether the Perl function you mentioned before starts threads,
like Tom suggested? That would be the probable cause, and the solution is
not to start any threads in a PostgreSQL function.

Yours,
Laurenz Albe