Re: High CPU Load - Mailing list pgsql-performance

From Scott Marlowe
Subject Re: High CPU Load
Date
Msg-id 1158249411.24726.17.camel@state.g2switchworks.com
Whole thread Raw
In response to Re: High CPU Load  ("Dave Dutcher" <dave@tridecap.com>)
Responses Re: High CPU Load  (Jérôme BENOIS <benois@argia-engineering.fr>)
List pgsql-performance
On Thu, 2006-09-14 at 10:02, Dave Dutcher wrote:
> > -----Original Message-----
> > From: pgsql-performance-owner@postgresql.org
> > [mailto:pgsql-performance-owner@postgresql.org] On Behalf Of
> > Jérôme BENOIS
> >
>  explain analyze select distinct
> > INTEGER_VALUE,DATE_VALUE,EI_ID,VALUE_TYPE,FLOAT_VALUE,ID,TEXT_
> > VALUE,CATEGORY_ID,STRING_VALUE,CATEGORYATTR_ID,NAME from (((
> > select distinct ei_id as EIID from mpng2_ei_attribute as
> > reqin1 where reqin1.CATEGORYATTR_ID = 0 AND reqin1.TEXT_VALUE
> > ilike '' and ei_id in ( select distinct ei_id as EIID from
> > mpng2_ei_attribute as reqin2 where reqin2.CATEGORYATTR_ID = 0
> > AND reqin2.TEXT_VALUE ilike '' and ei_id in ( select distinct
> > ei_id as EIID from mpng2_ei_attribute as reqin3 where
> > reqin3.NAME = '' AND reqin3.STRING_VALUE = '' ) ) ) ) ) as
> > req0 join mpng2_ei_attribute on req0.eiid =
> > mpng2_ei_attribute.ei_id order by ei_id asc;
>
>
> That is a lot of distinct's.  Sorts are one thing that can really use up
> CPU.  This query is doing lots of sorts, so its not surprising the CPU usage
> is high.

I'm gonna make a SWAG here and guess that maybe your 7.4 db was initdb'd
with a locale of C and the new one is initdb'd with a real locale, like
en_US.  Can Jérôme confirm or deny this?

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