Subject: Re: High CPU Load
From: =?ISO-8859-1?Q?J=E9r=F4me?= BENOIS <benois@argia-engineering.fr>
To: Markus Schaber <schabi@logix-tt.com>
Cc: pgsql-performance@postgresql.org,
	Xavier Milliard <milliard@argia.fr>
In-Reply-To: <450FEC1E.7080600@logix-tt.com>
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Date: Fri, 22 Sep 2006 09:43:52 +0200
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Hi, Markus,

Le mardi 19 septembre 2006 =C3=A0 15:09 +0200, Markus Schaber a =C3=A9crit =
:
> Hi, Jerome,
>=20
> J=C3=A9r=C3=B4me BENOIS wrote:
>=20
> >>> Now i Have 335 concurrent connections, i decreased work_mem parameter=
 to
> >>> 32768 and disabled Hyper Threading in BIOS. But my CPU load is still
> >>> very important.
> >> What are your settings for commit_siblings and commit_delay?
> > It default :
> >=20
> > #commit_delay =3D 01   # range 0-100000, inmicroseconds
> > #commit_siblings =3D 5 # range 1-1000
>=20
> You should uncomment them, and play with different settings. I'd try a
> commit_delay of 100, and commit_siblings of 5 to start with.
>=20
> > I plan to return to previous version : 7.4.6 in and i will reinstall al=
l
> > in a dedicated server in order to reproduce and solve the problem.
>=20
> You should use at least 7.4.13 as it fixes some critical buts that were
> in 7.4.6. They use the same on-disk format and query planner logic, so
> they should not have any difference.
>=20
> I don't have much more ideas what the problem could be.
>=20
> Can you try to do some profiling (e. G. with statement logging) to see
> what specific statements are the one that cause high cpu load?
>=20
> Are there other differences (besides the PostgreSQL version) between the
> two installations? (Kernel, libraries, other software...)
nothing.

I returned to the previous version 7.4.6 in my production server, it's
work fine !

And I plan to reproduce this problem in a dedicated server, and i will
send all informations in this list in the next week.

I hope your help for solve this problem.

Cheers,
J=C3=A9r=C3=B4me.

> HTH,
> Markus
--=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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