Message-ID: <46F2CB62.4020409@mochima.com>
Date: Thu, 20 Sep 2007 15:34:58 -0400
From: Carlos Moreno <moreno_pg@mochima.com>
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To: smiley2211 <smiley2211@yahoo.com>
CC: pgsql-performance@postgresql.org
Subject: Re: Upgraded from 7.4 to 8.1.4 QUERIES NOW SLOW!!!
References: <12803859.post@talk.nabble.com>
In-Reply-To: <12803859.post@talk.nabble.com>
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smiley2211 wrote:
> Hello all,
>
> Old servers that housed 7.4 performed better than 8.1.4 version...are there
> any MAJOR performance hits with this version???
>   

Are you using the default UNICODE encoding for your databases??
This could potentially translate into a performance hit  (considerable?
Maybe, depending on what your applications do)

A related question:  why not update to the latest, 8.2.x ??

> I set the postgresql.conf setting to equal that of 7.4 and queries still run
> SLOW on 8.1.4...
>   

Hmmm, I don't think the settings should be the same --- search the
archives for discussions on performance tuning and an informal
documentation of the postgresql.conf file.

> 3) vacuum analyze
>   

Am I understanding correctly that you did this??  Just to double check,
yes, it is *very* important that you analyze the database *after loading 
it*.

You could probably check the postgres log file to see if there are any
obvious red flags in there.

HTH,

Carlos
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