FW: Postgres cpu & memory usage

Hi All

I just wanted to follow up again from everyone to find out what is the
best way we can use to monitor the CPU and memory usage used by Postgresql.

We have a meeting tomorrow to discuss the hardware requirements for our
consolidated database server and we need these stats quite urgently.

As stated below the methods we are using are giving us inconsistent
results and I would really appreciate some help with this.

regards
Machiel

-----Original Message-----
From: pgsql-novice-owner(at)postgresql(dot)org
[mailto:pgsql-novice-owner(at)postgresql(dot)org] On Behalf Of machielr(at)rdc(dot)co(dot)za
Sent: 07 April 2010 11:54 AM
To: pgsql-novice(at)postgresql(dot)org
Subject: [NOVICE] Postgres cpu & memory usage

HI All

Some more questions from me today again ....

The client we are looking after wants to look at consolidating all
their databases onto one Database server.

Currently they have 16 Servers and a total of 190 Databases running
on these (even though a lot of them will be removed after the exercise
leaving about 90 odd).

They are also running application and web servers on the same
servers at the moment and the plan is to move all the databases onto
one central consolidated database.

However, in order to spec the server required, I need to create a
report of the system usage from a postgresql point of view.

I have configured pg_top on all the systems, however the info
received seems to be incorrect in the following sence:

- When running pg_top it show the cpu usage as 100% for user
however when running the linux top command this differs a lot.
- The linux top command (monitoring all postgres related
processes) totals not more than 5 % cpu usage and barely 1% memory
usage.

I am not sure how to get the correct information for postgresql
specifically.

Can anyoneone perhaps assist here?

Regards
Machiel