On Tue, Mar 13, 2012 at 5:42 PM, Bruce Momjian <bruce@momjian.us> wrote:
> What is the target=10 duration? I think 10 is as low as we can
> acceptably recommend. Should we recommend they run vacuumdb twice, once
> with default_statistics_target = 4, and another with the default?
I'm not sure why we're so glibly rejecting Dan's original proposal.
Sure, adjusting pg_upgrade when we whack around pg_statistic is work,
but who ever said that a workable in-place upgrade facility would be
maintenance-free? We're operating under a number of restrictions
imposed by the need to be pg_upgrade-compatible, and this doesn't
strike me as a particularly severe one by comparison -- we can always
arrange to NOT migrate statistics between incompatible versions; that
doesn't mean that we shouldn't migrate them when they ARE compatible.
Also, unlike the alternatives thus far proposed, Dan's idea actually
fixes the problem.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company