Thread: BUG #5990: 100% CPU reached

The following bug has been logged online:

Bug reference:      5990
Logged by:          Allen Sooredoo
Email address:      allen_sooredoo@carrefour.com
PostgreSQL version: 8.4
Operating system:   Windows Server 2003
Description:        100% CPU reached
Details:

Hi,
we are facing a performance issue on Postgres 8.4, the CPU reaches 100% with
less than 50 simultaneous users.

We were thinking to migrate the HR system from Oracle to Postgres but now
that we have those big performance problems on relatively small
applications, we are questioning this choice.

The machine configuration, dedicated to Postgres is as follow:
RAM: 3GB
CPU: Intel Xeon CPU 3.2 Ghz

Could you please provide us some support regarding this issue?

Regards

"Allen Sooredoo" <allen_sooredoo@carrefour.com> wrote:

> we are facing a performance issue on Postgres 8.4, the CPU reaches
> 100% with less than 50 simultaneous users.
>
> We were thinking to migrate the HR system from Oracle to Postgres
> but now that we have those big performance problems on relatively
> small applications, we are questioning this choice.
>
> The machine configuration, dedicated to Postgres is as follow:
> RAM: 3GB
> CPU: Intel Xeon CPU 3.2 Ghz
>
> Could you please provide us some support regarding this issue?

Since many people are using PostgreSQL with large databases and many
users, it's important to understand what it is about your particular
situation which is causing it not to perform well.  (Our shop, for
example, has a 2 TB database with millions of hits per day.)

Please read this and post to the pgsql-performance list:

http://wiki.postgresql.org/wiki/SlowQueryQuestions

You will probably get the most useful responses if you can first
identify one or more of your slow queries and post the specifics of
those, per the above web page.

-Kevin

* Kevin Grittner (Kevin.Grittner@wicourts.gov) wrote:
> > Could you please provide us some support regarding this issue?
[...]
> Please read this and post to the pgsql-performance list:
>=20=20
> http://wiki.postgresql.org/wiki/SlowQueryQuestions

If that looks like a lot of complication/effort, let's at least start
with including what the hardware is (how much memory, how many CPUs,
what disk configuration, etc) and your postgresql.conf.  The defaults
for postgresql.conf are almost always wrong for a given hardware (unless
you're running on a Celeron w/ 1G of RAM...).

    Thanks,

        Stephen