Topic: Mercury LoadRunner Testing Tool

Mercury LoadRunner Testing Tool

Mercury LoadRunner is a load testing product that determines application scalability, behavior, and performance. It emulates thousands of virtual users and identifies and isolates performance bottlenecks across and within each tier.

LoadRunner components
LoadRunner contains the following components
Virtual User Generator (VuGen): Records Vuser scripts that emulate the steps of real users using the application. In testing environment the LoadRunner replaces human users with virtual users (Vusers). Vusers create load by emulating actions of typical users. VuGen works on record and playback principle. You have to walk through a business process or test process on your application which is recorded by VuGen into scripts. Then you can run these scripts n times simulating the test case of n users performs that particular business process simultaneously.
Controller: The administrative center for creating, executing and monitoring Scenarios. It provides you the tools to create the scenarios. Or in other words you can set attributes of your scenarios here (like think time). For example you may want 10 users log into a system simultaneously, you can use rendezvous event.
Analysis: Uses the Load Test results to create graphs and reports. This is to identify bottlenecks and performance issues or any other failures in your system’s performance and then pinpoint the source of these failures.

Understanding Load Runner Terminology
Scenarios - A scenario identifies the scripts to execute, the number of Vusers, goals of the test and the conditions under which to run the tests.
Vusers - Vusers emulate the actions of human users working with your application. A scenario can contain tens, hundreds, or even thousands of Vusers.

Vuser Scripts - The actions that a Vuser performs during the scenario are described in a Vuser script.
Transactions - To measure the performance of the server, you define transactions. A transaction represents end-user business processes that you are interested in measuring.
Load Generators – They are dedicated machines which are used to run the Vusers that generate load on the application under test.