On 2016-05-18 18:42:16 -0400, Tom Lane wrote: > Andres Freund <and...@anarazel.de> writes: > > On 2016-05-18 18:25:39 -0400, Tom Lane wrote: > >> Yes, I've been wondering that too. VACUUM is not meant as a corruption > >> checker, and should not be made into one, so what is the point of this > >> flag exactly? > > > Well, so far a VACUUM FREEZE (or just setting vacuum_freeze_table_age = > > 0) verified the correctness of the visibility map; and that found a > > number of bugs. Now visibilitymap grew additional responsibilities, > > with a noticeable risk of data eating bugs, and there's no way to verify > > whether visibilitymap's frozen bits are set correctly. > > Meh. I'm not sure we should grow a rather half-baked feature we'll never > be able to remove as a substitute for a separate sanity checker. The > latter is really the right place for this kind of thing.
It's not a new feature, it's a feature we removed as a side effect. And one that allows us to evaluate whether the new feature actually works. -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers