This is the critical point. You have this line: There were 132969 unused item pointers.
Which says there's 132k or so dead rows in your table. Which means vacuum / autovacuum isn't keeping up. Did you try and stop the update several times? Each time it starts then gets killed it creates dead rows. Try doing a vacuum full followed by a reindex OR a cluster on this table and see if that helps. -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
