Re: Query time

Michael Fuhr wrote:

>On Fri, Mar 10, 2006 at 11:05:57AM +0100, Ruben Rubio Rey wrote:
>
>
>>Sometimes some big query takes between 5 to 15 seconds. It happens
>>sometimes all the day it does not depend if database is busy.
>>
>>I have measured that sentence in 15 - 70 ms in normal circunstances.
>>
>>
>
>Is it the *exact* same query, including the values you're querying
>for?  The same query with different values can run with different
>plans depending on row count estimates.  It might be useful to see
>the query string and the EXPLAIN ANALYZE output for a fast query
>and a slow one.
>
>How many tables are you querying?  Might you be hitting geqo_threshold
>(default 12)?  If so then the following thread might be helpful:
>
>http://archives.postgresql.org/pgsql-performance/2006-01/msg00132.php
>
>
>

The querys that are failing are very similar. But, when I see the
warning in logs files, I take that query and try it, and takes a few
miliseconds (as spected). That query one table on FROM and 2 or 3 on
WHERE clause.

Rigth now Im using the default server configuration for geqo_threshold,
but i'll ckeck the link that u provide me.