You use the Rational Performance Tester workbench to distribute the user load. When you distribute the load among agent computers, you should remember the load each agent computer can take efficiently. For information about capacity planning, see the Capacity planning topic.
Rational Agent Controller is used to gather data for the Response Time Breakdown feature and in support of the startup and control of web services stubs in the SOA protocol. The Load Generation Agent is used to generate load for the application under test by using the virtual users.
When installing Rational Performance Tester Agent, you can specify the hostname of the workbench to poll. After the installation, the agent automatically connects to the workbench. If you want to share the agent with multiple workbenches, you can either manually add them to the majordomo.config file located at installationDir/Majordomo or use the Share Agent with New Workbench option mentioned in the Checking status of agents topic.
When you run a schedule with multiple agents, an agent might be lost, especially during the long load test run. Losing an agent is not common and occurs during some extreme cases such as when computer's memory is exhausted. When an agent is lost, by default, the schedule is stopped. When the schedule is stopped in this manner, you must fix the reason of agent loss or add more agents before running the schedule. To continue to run the schedule without the lost agent, in the Schedule editor, click the Advanced tab and clear the Loss of an agent halts execution check box. Typically, the agents divide the load among themselves. So, running a schedule without the lost agent might give unpredictable results. If you use a segmented datapool and if you run a schedule without the lost agent, the data is not redistributed among the surviving agents. Also, if the schedule has multiple stages, by default, the user load is distributed among the surviving agents at the next stage. But, if the Replace lost users in current stage check box is selected, then the user load is distributed evenly among the surviving agents in the current stage. If the check box is cleared and a percentage of users are allowed to exit during stage execution, the user load is distributed among the surviving agents in the next stage. Loss of an agent in a schedule run is logged in the Performance Report.
- You can install Rational Performance Tester and Rational Performance Tester Agent on any of the supported platforms mentioned in the Software requirements topic. It is not necessary that both are installed on the same platforms or the bitness of the platform must be same.
- If you creating load on the Rational Performance Tester Agent machine, ensure that, in the workbench, you clicked Run user group at a remote location and pointed to the agent machine.
- If you are using Rational Performance Tester workbench 8.3 or later, you must use Rational Performance Tester Agent 8.3 or later. Also, it is recommended to use the same release version for both.
The Rational Performance Tester workbench automatically deploys test assets required for execution to participating agents. For more information about the deployment directory, see Managing deployment directory.
A typical set up of Rational Performance Tester workbench, Rational Performance Tester agents,
and the system under test is shown here: