Thursday, 9 February 2012

Loadrunner components - Vugen, Controller, Analysis

Loadrunner components 

 Loadrunner has mainly three components.
  • VuGen (Virtual user generator)
  • Controller (License based component)
  • Analysis
Apart from these components there are other components like LoadRunner Agent process.
The purpose of Vugen is to create scripts for single user and do the required enhancements to the script in a such a way that it can be run for multiple users.
The purpose of Controller is to Run the load test and monitor the servers during load test execution. In loadrunner language is to create scenarios and the run the loadrunner controller scenario. Generally Controller installed in a client environment machine which will be configured with loadrunner license for defined number of users. Performance engineers to connect to this machine to run the load test. If the client has multiple projects and multiple performance engineer resources, client may setup mutiple controller with multiple licenses.
Analysis will be used to Analyze the results and creare graphs and reports to present the performance test report to stake holders.

File Extensions:
VuGen        :     .USR is the file extension.
Controller   :     .lrs  is the file extension. - -> .lrr 
Analysis      :     .lra is the file extension

Loadrunner environment:
Number of machines required in loadrunner test environment. In general you can use one machine by installing all the components one box.
  • 1 Machine: Controller, Vugen, Anaylysis and Loadrunner agent process. The disadvantage is we may not able to run bigger load test. 
  • Multiple Machine:
    • Controller1 - 1 Machine - 1000 user license
    • Load generators  - 3 Machines
    • Controller2 - 1 Machine - 3000 user license 
    • Load generators  - 3 Machines
    • Controller4 - 1 Machine - 2000 user license
    • Load generators  - 3 Machines
Performance Center: 
In performance Center License will be calcuate on cumulative basis and this is one of the best feature in Performance center.