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.
