Greg Stark <gsstark(at)mit(dot)edu> writes:
> Does this create a problem combined with the plan to allow the new
> VACUUM FULL to rewrite system tables? From my brief scan it sounds
> like the only reason there's no race condition here is that previously
> the oid of system tables couldn't change out from under
> load_critical_index.
Their OIDs will never change, so I don't see an issue. Locks are taken
on OIDs not relfilenodes, so a relocation doesn't break locking. If
it did we'd already have a problem with relocating user tables.
regards, tom lane