Josh Berkus <j...@agliodbs.com> writes: > From a discussion at dinner at pgcon, I wanted to send this to the list > for people to poke holes in it:
Somebody (I think Joe or Heikki) poked a big hole in this last night at the Royal Oak. Although the scheme would get rid of the need to replace old XIDs with FrozenXid, it does not get rid of the need to set hint bits before you can truncate CLOG. So in your example of an insert-only table that's probably never read again, there's still a minimum of one update visit required on every old page. Now that's still better than two update visits ... but we could manage that already, just by tweaking vacuum's heuristics about when to freeze vs when to set hint bits. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers