Chris Browne <cbbrowne@acm.org> writes:
> There isn't any way, short of restarting the postmaster, to get rid of
> that PID, is there?
The entry will get overwritten when that BackendId slot gets re-used,
so just starting enough concurrent backends should do it. (Since
incoming backends always take the lowest free slot, the fact that the
dead entry has persisted awhile means that it must have a number higher
than your normal number of concurrent sessions ... which is evidence
in favor of the idea that it happened during a load spike ...)
regards, tom lane