Re: add_path optimization

From: "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov>
To: "Robert Haas" <robertmhaas(at)gmail(dot)com>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: add_path optimization
Date: 2009-02-03 01:10:29
Message-ID: 49874525.EE98.0025.0@wicourts.gov
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

>>> 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

-Kevin

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message KaiGai Kohei 2009-02-03 01:28:22 Re: How to get SE-PostgreSQL acceptable
Previous Message Robert Haas 2009-02-03 00:55:31 Re: How to get SE-PostgreSQL acceptable