Rod Taylor <rod.taylor@gmail.com> wrote:
> Would pg_dump be able to opt-out of such a restriction?
I don't see how, since vacuum would be removing recently dead
tuples that are still visible; the alternative to getting a
"snapshot too old" error when reading a page which could be
affected is to return incorrect results, and nobody wants that.
The best you could do if you wanted to run pg_dump (or similar) and
it might take more time than your old_snapshot_threshold would be
to increase the threshold, reload, dump, set it back to the
"normal" setting, and reload again.
Andrew's suggestion of setting this per table would not help here.
--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company