Load generators are the machines that run the Vuser scripts in your scenarios. Each Vuser script that runs on a load generator results in a single Vuser. Each load generator can run multiple Vuser scripts, thereby resulting in multiple Vusers. While these Vusers run, they create load on your system, enabling you to analyze your system under load.
Creating load generators
To create a load generator, you install the LoadRunner load generator software on a host computer. Load generators can be either Windows-based or Linux-based. For Docker platforms, you can use one of the available Dockerized load generator images (see Configure Dockerized load generators).
For details on how to install the appropriate load generator software, see the Installation guide.
Note: The LoadRunner Professional standalone load generator and standalone monitor over firewall (MOFW SA) cannot be installed on the same machine. However, the load generator can be used for monitoring purposes, the same way as the MOFW SA. Note that a single machine cannot be used simultaneously for both running Vusers and monitoring.
Including load generators in a scenario
After you have installed the load generator software on a host computer to create a load generator, you can include the new load generator in a scenario. You use Controller to add the new load generator to a scenario.
To enable a scenario to develop significant load on a system, a typical scenario may include multiple load generators. You define and maintain the list of load generators that are available in a scenario. When you add a load generator to the list of load generators in a scenario, you define various attributes of the load generator, such as the platform on which the load generator runs. You can modify some - but not all - of these attributes after the load generator is created.
Enabling and disabling a load generator
If a specific load generator is included in the list of load generators for a scenario, but is temporarily unavailable for a particular scenario run, you can disable the load generator instead of removing it permanently from the list. You can then enable the load generator if and when it becomes available.
Connect/Disconnect a load generator
To manually connect or disconnect a load generator, on the Controller toolbar, click Load Generators.
Select a load generator in the list and click Connect/Disconnect.
The Windows installer package included with LoadRunner Professional, OneLG, is a combined load generator installer for all of the LoadRunner family products. During installation, you select the relevant product, and the load generator is installed with the appropriate configurations for that flavor.
Each load generator flavor has the following setup:
- LoadRunner Professional (LRP). After load generator installation, by default the LoadRunner Agent runs as a process (magentproc.exe).
- LoadRunner Enterprise (LRE). After load generator installation, by default the LoadRunner Agent runs as a service (agentservice.exe).
LoadRunner Cloud (LRC). Load generator installation includes defining LoadRunner Cloud configuration settings. After load generator installation, by default the LoadRunner Agent runs as a service (though this is not relevant for LoadRunner Cloud processes).
After a load generator is installed, you have the option to switch the load generator to work with a different tool from the LoadRunner family. This may involve reconfiguring load generator settings, using the following shortcut options available from the machine Start menu:
LoadRunner Agent Runtime Settings. Opens the LoadRunner Agent Runtime Settings dialog box, where you can define login parameters to use when switching from manual process to service.
For details, see LoadRunner Agent Runtime Settings dialog box.
LoadRunner Cloud - Configure Load Generator. Opens the LoadRunner Cloud load generator configuration tool, where you configure settings for the LoadRunner Cloud Agent.
For details, see the load generator configuration tool documentation in the LoadRunner Cloud Help Center.
- LoadRunner Agent Service. Switches the LoadRunner Agent to run as a service.
- LoadRunner Agent Process. Switches the LoadRunner Agent to run as a manual process.
The actions required to switch load generator flavor are as follows:
|Installed flavor:||To use with:|
|LRP||No action required||Switch to service||Configure LRC Agent|
|LRE||No action required||No action required||Configure LRC Agent|
|LRC||No action required||No action required||No action required|
Caution: When using LoadRunner Professional, there are some specific protocols that require the LoadRunner Agent to run as a process.
Local versus cloud-based load generators
A load generator can be located on either a local computer or in the cloud. A scenario can include both local and cloud-based load generators. The procedure for defining and maintaining load generators is similar for local and cloud-based load generators. For details, see Add load generators to a scenario.
Load generator configuration
To create and run accurate real-life scenarios, you can configure numerous settings for each load generator that is included in a scenario. For details, see Modify load generator settings.
Status of a load generator
Controller's Load Generators dialog box shows the status of each load generator in a scenario. The status of a load generator changes during a scenario run. For example, when you add a load generator to the list of load generators in a scenario, the load generator has the status Down. The status of the load generator changes to Ready when the load generator is connected to Controller and is available to run Vuser scripts, and then to Running while the load generator executes a Vuser script. For a full list of load generator statuses, see Load Generators dialog box.