On few large DBs we run vacuum analyze manually as well, and I do see few people vacuuming the template1 db or postgres db also
So just wanted to know vacuum system dbs is required or not?
Pretty sure the answer is yes - though letting auto-vacuum do it is sufficient - since something has to update the catalog column that indicates the oldest transaction the database is aware of. There isn't a value for that which means "everything has been frozen" since it doesn't get updated in the normal course of activity.
