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Re: Low CPU Usage

From: brauagustin-susc(at)yahoo(dot)com(dot)ar
To: Kevin Grittner <Kevin(dot)Grittner(at)wicourts(dot)gov>, pgsql-performance(at)postgresql(dot)org
Subject: Re: Low CPU Usage
Date: 2007-09-21 18:20:30
Message-ID: 582823.746.qm@web30009.mail.mud.yahoo.com (view raw or flat)
Thread:
Lists: pgsql-performance
> That's not what it looks like based on the EXPLAIN ANALYZE output.
> It looks like run time dropped from two seconds to half a second.
 
> It seems as though you either have a network delay delivering the results,
> or your application is slow to read them.

> Exactly how are you arriving at those timings you're reporting to us?
 
I have noticed this in a daly process I run which involves normally 45 minutes and with the new server takes 1:40.

Some days ago I began to do some tests with no success, then I opened PgAdmin with this simply query to read 2 big tables and then compare disk access.
SELECT *
FROM fact_ven_renta fvr, dim_producto_std_producto dpp
WHERE
  fvr.producto_std_producto_sk = dpp.producto_sk
 
fact_ven_renta has 136316 rows
dim_producto_std_producto has 3669 rows



I have made all possible combinations pgadmin (running in the same server each query, in the old one, in the new one), without difference  and I only retrieve the first 100 records (I didn't count the network time in any case).
But the weird thing is running the query in the new server the are many disk access and cpu usage. And with other applications in the same server are a lot of disks access.






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Subject: Re: Low CPU Usage
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