Re: add_path optimization

Robert Haas wrote:
> On Mon, Feb 2, 2009 at 8:10 PM, Kevin Grittner
> <Kevin(dot)Grittner(at)wicourts(dot)gov> wrote:
> >>>> Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> >> running this 5 times each on several queries,
> >> dropping top and bottom results.
> >
> > Running a complex query (posted in previous threads, runs about
> > 300,000 time per day in a production web application), I got these
> > timings on a production quality machine (4 quad CPU chips, that is 16
> > CPUs like this: Intel(R) Xeon(R) CPU X7350 @ 2.93GHz, 128 GB RAM, big
> > RAID with BBU). I ran explain in each environment 5 times, tossed
> > high and low, and averaged. The 8.4devel was from today's
> > (2008-02-02) snapshot, built the same way we did 8.3.5.
> >
> > 8.3.5, statistics target 10: 36.188 ms
> > 8.4devel without patch, statistics target 100: 109.862 ms
> > 8.4devel with patch, statistics target 100: 104.015 ms
> >
> > After seeing that, I re-analyzed to eliminate the statistics target as
> > the cause of the 8.4 increase.
> >
> > 8.4devel with patch, statistics target 10: 99.421 ms
>
> Yikes! The impact of the patch is about what I'd expect, but the fact
> that planning time has nearly tripled is... way poor. Can you repost
> the query and the EXPLAIN output for 8.3.5 and CVS HEAD?

Where are we on this: the original patch, and Kevin's slow queries?

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +