On Monday, February 17, 2025, Hayato Kuroda (Fujitsu) < kuroda.hay...@fujitsu.com> wrote:
> > backend> SELECT pg_create_physical_replication_slot(slot_name := > 'physical_slot', immediately_reserve := true); Since this function releases the slot when it returns, re-acquisition, even by the same backend, must always re-associate MyProcPid to the named slot. > > [1]: > ``` > --- a/src/backend/replication/slot.c > +++ b/src/backend/replication/slot.c > @@ -599,7 +599,7 @@ retry: > SpinLockRelease(&s->mutex); > } > else > - active_pid = MyProcPid; > + s->active_pid = active_pid = MyProcPid; > LWLockRelease(ReplicationSlotControlLock); > > /* > ``` > This, but you cannot modify the slot without holding the spinlock. I’d probably add an assert that the existing state of s->active_pid is either 0 or MyProcPid already. In single-user mode it mustn’t, really cannot, be anything else. But the failure here is because the SQL function does a slot release; there are probably other reasonable paths where the assignment of MyProcPid during slot creation is retained and encountered during a subsequent slot acquire. David J.
