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Message-ID: <1d4e0c10609141422o57ecf28eobf3d0b7594bb242f@mail.gmail.com>
Date: Thu, 14 Sep 2006 23:22:48 +0200
From: "Guillaume Smet" <guillaume.smet@gmail.com>
To: "=?ISO-8859-1?Q?J=E9r=F4me_BENOIS?=" <benois@argia-engineering.fr>
Subject: Re: High CPU Load
Cc: "Scott Marlowe" <smarlowe@g2switchworks.com>,
	"Dave Dutcher" <dave@tridecap.com>, pgsql-performance@postgresql.org
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References: <004001c6d80e$bdef5bc0$8300a8c0@tridecap.com>
	<1158249411.24726.17.camel@state.g2switchworks.com>
	<1158268058.5167.2.camel@localhost.localdomain>

J=E9r=F4me,

Perhaps it's a stupid question but are your queries slower than
before? You didn't tell it.

IMHO, it's not a problem to have a high load if you have a lot of
users and your queries are fast (and with 8.1, they should be far
faster than before).

To take a real example, we had a problem with a quad xeon running
postgres 7.4 and even when there were a lot of queries, the load was
always lower than 4 and suddenly the queries were really slow and the
database was completely unusable.
When we upgraded to 8.1, on very high load, we had a far higher cpu
load but queries were far faster even with a high cpu load.

Considering your top output, I suspect you use HT and you should
really remove it if it's the case.

--
Guillaume