"Greg Rychlewski (LCL)" <Greg.Rychlewski@loblaw.ca> writes:
> Thanks for your reply. Regarding it being blocked, I don't think it is but I could be wrong. Both wait_event and
wait_event_typeare null. One thing I noticed though is that n_dead_tup in pg_stat_all_tables either stays the same or
goesup. Should this be going down during the autovacuum?
No ... ongoing transactions could be creating new dead rows. IIRC,
a vacuum won't report its removal of dead rows to the stats collector
till the very end, so what I'd expect is a big drop when it finishes.
(I am not sure offhand what happens to those stats if you cancel the
vacuum partway through --- it might report nothing, causing the
stats to be way off until the next successful vacuum.)
regards, tom lane