All,

We are using FB 1.5 to run an application to simulate Business
situation and found out a very strange performance situation that
introduced a bottleneck in our project.
We are using the following:
1) A network with 5 computers (running at 100 Mb network)
2) One of the microcomputers in the network is a database server
without other usage.
3) All computers are Pentiun 4 2.4 HT. All have 1Gb of memory and 80
Gb hard-drive.
4) We are using windows 2000 with the current Microsoft Service Pack
installed.
5) No other application but the simulation are running in the system.
6) The application were developed with Delphi 6 and DBExpress.

The strange performance is the following:

1) Running only one client (one microcomputer accessing the database)
the process last 2 minutes (we implemented a log to record the start
and finish of the operation).
2) Running 4 (four) clients (four microcomputer accessing the
database) the process last 8 minutes (all processes finished at
almost the same time showing that they are running at once).

We expected a little bit time using 4 clients (like 2.5 or 3 minutes)
but not exactly 4 times to run the application.

We checked all the application (it is very huge and have a lot of SQL
doing a lot of work) and everything is according the rules.
We tryed to change the client (at first we had only one user for all
client and changed it for 4 different users) without any changes in
the performance.
We changed the page size from 1k to 10k and nothing happened in the
performance.

This project was designed to run 100 clients simultaneously and with
this performance it will last 200 minutes to run what is not
acceptable.

Can someone provide me some clue how to solve this? Or provide me
some explanation why it is happening and if I need to change
something like Delphi, FB, OS, etc?

Thank you for your help, and comments,

Wagner Bazarin
Sao Paulo
Brazil