Noah Misch <n...@leadboat.com> writes: > Just a suspicion ... when looking at the B-tree page reclamation algorithm, I > had a thought that the logic in _bt_page_recyclable() was obsolete as of the > introduction (in 8.3) of xid-free read-only transactions. A transaction > without a persistent xid does not hold back RecentXmin, so how could waiting > for a RecentXmin window to pass prove that no scan still holds a link to the > page? Similarly, running VACUUMs do not hold back RecentXmin.
Uh, sure they do. It's their advertised snapshot xmin that counts, not their own xid (if any). 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