LoadRunner Architecture

Following are the Major components of LoadRunner

• Vugen
• Controller
• Load Generator
• Analysis

 

Vugen

Virtual User Generator (or) Vugen is the IDE (Integrated Development Environment) which  is used to record end-user business processes and it generats script known as Vuser Script. It records the traffic between client server communication and generates the script. After the script is generated enhancements were made based on the requirements. Some of the enhansements will be Correlation, parameterization, inserting transactions, thinktime, write custom code, insert validations, etc.

Controller

The Controller is one of  the component of loadrunner. Workload is designed in the controller by allocating number of users for each scenerio.It also defines the user behaviour ,the main task of the controller is to controller the users as per work load design and collect the data from LGs and give it to analasis.

Load generator

Load generators are the machines which are responsible to generate the load of multiple users on the system. We can use any number of load generators during the test. For Http protocol each user consumes 2 MB of memory to simulate single virtual user so,to run 1000 virtual users we need 2GB approxmatly.

Analysis

After the test run Analysis component creates the graphs based on the data in output.mdb file. There are different graphs which states different values; like Running Vusers, Throughput, Hits/sec, Pages/min, Tracsactions/sec, Average Transaction Response Time, etc.

Other components includes :

Remote Agent Dispatcher – Remote Agent Dispatcher(Process) enables the Controller to start applications on Load Generator(s).

LoadRunner Agent – It communicats and manages the connection between the Controller and Load Generator(s). When the scenario is run, the Controller instructs the Remote Agent Dispatcher(Process) to launch the LoadRunner agent. The agent receives the instructions from Controller to initialize, run, pause, and stop Vusers. It also send back the data of the status of the Vusers back to the Controller.