Re: %100 CPU on Windows Server 2003

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

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Hello

please, can you attach a value of shadow_buffers and work_mem from config
file?

Windows are very sensitive on memory setting. There must be lot of memory
just for MS Windows.

Regards

Pavel Stehule

2011/4/20 Allen Sooredoo <Allen_Sooredoo(at)carrefour(dot)com>

> 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
>
>
>
> *This e-mail and any attachment are confidential and intended solely for
> the use of the individual to whom it is addressed. If you are not the
> intended recipient, please telephone or email the sender and delete this
> message and any attachment from your system. Unauthorized publication, use,
> dissemination, forwarding, printing or copying of this e-mail and its
> associated attachments is strictly prohibited.
> http://disclaimer.carrefour.com
> Let's respect the environment together. Only print this message if
> necessary *
>

On Wed, Apr 20, 2011 at 10:55 AM, Allen Sooredoo <
Allen_Sooredoo(at)carrefour(dot)com> wrote:

> 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?
>

Probably, but you'll need to provide more details. It is likely that you
have some queries that need to be tuned, and possibly some settings that
need to be changed. But without some information about what is using up all
the CPU time, it's hard to speculate as to what the problem might be.

http://wiki.postgresql.org/wiki/Guide_to_reporting_problems

You might also want to read this article:

http://www.linux.com/learn/tutorials/394523-configuring-postgresql-for-pretty-good-performance

I've also found that log_min_duration_statement is pretty useful for
figuring out where the CPU time is going - it helps you find your
long-running queries.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company