Re: query rewrite using materialized views - Mailing list pgsql-performance

From Josh Berkus
Subject Re: query rewrite using materialized views
Date
Msg-id 200501041337.27884.josh@agliodbs.com
Whole thread Raw
In response to Re: query rewrite using materialized views  (Rod Taylor <pg@rbt.ca>)
List pgsql-performance
Ryan,

> >   I do this, PG gets forked many times, it is tough to find the max
> > number of times I can do this, but I have a Proc::Queue Manager Perl
> > driver that handles all of the copy calls.  I have a quad CPU machine.
> > Each COPY only hits ones CPU for like 2.1% but anything over about 5
> > kicks the load avg up.

That's consistent with Xeon problems we've seen elsewhere.   Keep the # of
processes at or below the # of processors.

Moving pg_xlog is accomplished through:
1) in 8.0, changes to postgresql.conf
    (in 8.0 you'd also want to explore using multiple arrays with tablespaces to
make things even faster)
2) in other versions:
    a) mount a seperate disk on PGDATA/pg_xlog, or
    b) symlink PGDATA/pg_xlog to another location

--
--Josh

Josh Berkus
Aglio Database Solutions
San Francisco

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