Re: Race conditions in 019_replslot_limit.pl

Andres Freund <andres@anarazel.de> writes:
> But right now I'm not seeing what prevents us from throwing a FATAL error
> while holding an lwlock?

If we're inside a transaction, then ShutdownPostgres ->
AbortOutOfAnyTransaction would release LWLocks.  I wonder
though if an exiting walsender would always take that path.
Maybe it'd be good if we released all LWLocks even if we
don't think we're in a transaction?

More generally, it wasn't obvious to me why you thought that
BaseInit was a good spot to place the on_shmem_exit call.
It obviously can't be *before* that because of the pgstats
dependency, but maybe it should be later?

            regards, tom lane