Jeff Janes <jeff.janes@gmail.com> wrote:
> But I do wonder what experience people have with the 3 stage
> process, how useful is it empirically? If you can't open the
> database for general use until the 3rd phase is done, then you
> would just jump to doing that stage, rather than working through
> all 3 of them. If you can open the database and muddle through
> without statistics for a while, why not muddle through for the
> little bit longer that it would take to collect the full set
> right off the bat, rather than making intermediate passes?
It's not always a "little bit" of time. For a description of my
experience with a home-grown 3 stage process before one was built
into pg_upgrade, see this post:
http://www.postgresql.org/message-id/1373465348.51692.YahooMailNeo@web162906.mail.bf1.yahoo.com
Basically, we cut our down time from hours to minutes without
serious impairment of performance.
--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
