Subject: Re: High CPU Load
From: =?ISO-8859-1?Q?J=E9r=F4me?= BENOIS <benois@argia-engineering.fr>
To: Guillaume Smet <guillaume.smet@gmail.com>
Cc: Scott Marlowe <smarlowe@g2switchworks.com>,
	Dave Dutcher <dave@tridecap.com>, pgsql-performance@postgresql.org,
	Xavier Milliard <milliard@argia.fr>
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	<1158249411.24726.17.camel@state.g2switchworks.com>
	<1158268058.5167.2.camel@localhost.localdomain>
	<1d4e0c10609141422o57ecf28eobf3d0b7594bb242f@mail.gmail.com>
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Date: Thu, 14 Sep 2006 23:48:42 +0200
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Hi Guillaume,

Le jeudi 14 septembre 2006 =C3=A0 23:22 +0200, Guillaume Smet a =C3=A9crit =
:
> J=C3=A9r=C3=B4me,
>=20
> Perhaps it's a stupid question but are your queries slower than
> before? You didn't tell it.
No, it's not stupid question !
Yes queries speed but when the load average exceeds 40 all queries are slow=
er than before.

> 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).
Yes i have a lot of users ;-)
>=20
> 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.

I agree but by moment DB Server is so slow.

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

what's means "HT" please ?

> --
> Guillaume

If you want, my JabberId : jerome.benois AT gmail.com

--=20
J=C3=A9r=C3=B4me,

python -c "print '@'.join(['.'.join([w[::-1] for w in p.split('.')]) for
p in 'sioneb@gnireenigne-aigra.rf'.split('@')])"

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