The installation tuning tests were created to quickly and
conveniently apply load to an application server for the purpose of
tuning the application server for maximum throughput. The three tests
that are provided stress various parts of the application server.
The installation tuning tests are designed to test
IBM® WebSphere® Application Server Version
7. Each test has different requirements that must be met before you
run the test.
- The Schedule_Snoop test is ready to use with any WebSphere Application Server installation.
- The "Schedule_Plants: PlantsByWebSphere" sample application must
be installed. The sample application is provided with WebSphere Application Server,
but its installation is optional.
- The Schedule_Daytrader test application is freely available from
the Apache project Geronimo. Daytrader requires access to an IBM DB2
database.
Best results can be achieved for all tests by using
one or more separate, dedicated computers to provide the greatest
possible loads on the application server. When testing a large WebSphere Application Server application,
a single computer that runs Rational® Performance Tester and
provides a load on the application might not provide sufficient stress
to test the application.
An installation tuning test is designed
to stress your application server to achieve maximum throughput from
basic tuning. Tuning is a complex procedure with many possible adjustments
available according to the varying requirements of the application
that you plan to run. For more information on tuning WebSphere Application Server,
see http://www.ibm.com/developerworks/websphere/techjournal/0909_blythe/0909_blythe.html.
A
simple goal when you run the installation tuning tests is to achieve
the highest percentage of CPU utilization on the application server
while the test runs. Follow these guidelines as you run each test:
- Use Task Manager, vmstat, or a similar tool to observe CPU utilization
on the computer that runs the application server. With maximum throughput
as a goal, you work to achieve the highest CPU percentage possible.
To achieve maximum throughput, this number must increase as you make
tuning adjustments.
- Monitor the CPU utilization of the computer that runs Rational Performance Tester.
If CPU utilization exceeds 70%, you might be approaching the limits
of what that computer can provide. However, Rational Performance Tester supports
using multiple computers to achieve an even greater load.
- Because these tests provide high throughput, the tests might exceed
the capabilities of your network. A tool such as Task Manager can
show network utilization. If you are limited by a 100 Mbps network,
access to a 1000 Mbps network might be required to fully stress the
application server.