Tom Lane wrote: > Bruce Momjian <br...@momjian.us> writes: > > We often mention that we do vacuum freeze for anti-wraparound vacuum, > > but not for pg_clog file removal, which is the primary trigger for > > autovacuum vacuum freezing. I have added the attached documentation > > patch for autovacuum_freeze_max_age; back-patched to 9.0. > > This patch does not actually seem like an improvement. The paragraph is > all about transaction age, but you've inserted something entirely > unrelated, and not only that but chosen to make the unrelated thing seem > like the major consequence and anti-wraparound an afterthought.
Well, the reason that value is 200 million is for pg_clog cleanup, not for xid wraparound protection. The next sentence does relate to xid wraparound, but it seems to fit because the previous sentence ends with xid wraparound: Note that the system will launch autovacuum processes to prevent wraparound even when autovacuum is otherwise disabled. If we were worried about just xid wraparound I assume the value would be 2 billion. Do you have a suggestion? Reorder the items? -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + It's impossible for everything to be true. + -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers