LoadRunner
From Wikipedia, the free encyclopedia
- For the video game, see Lode Runner.
- For the Citroen CX Loadrunner, see Citroën_CX.
LoadRunner is a performance and load testing product by Hewlett-Packard (since it acquired Mercury Interactive in November 2006) for examining system behavior and performance, while generating actual load. LoadRunner can emulate hundreds or thousands of concurrent users to put the application through the rigors of real-life user loads, while collecting information from key infrastructure components (Web servers, database servers etc). The results can then be analysed in detail, to explore the reasons for particular behaviour.
Consider the client-side application for an automated teller machine. Although each client is connected to a server, in total there may be hundreds of ATMs open to the public. There may be some peak times — such as 10 a.m. Monday, the start of the work week — during which the load is much higher than normal. In order to test such situations, it is not practical to have a testbed of hundreds of ATMs. So, if we have an ATM simulator and a computer system, with LoadRunner, we can simulate a large number of users accessing the server simultaneously. Once activities have been defined, they are repeatable. After debugging a problem in the application, managers can check whether the problem persists by reproducing the same situation, with the same type of user interaction.
Working in LoadRunner involves using three different tools which are part of LoadRunner. They are Virtual User Generator (VuGen), Controller and Analysis.
VuGen The VuGen allows a user to do the scripting of the application to undergo the test and enables the performance tester to playback and make modifications to the script as needed. The modifications involves activities like Parameterization(Providing data for runtime), Correlation and Error handling.
Controller Once a script is prepared in Vugen, it is run via the Controller. Each run is called as a scenario with some preset settings. Loadrunner provides the usage of various machines to act as LoadGenerators, i.e., to run a test of 100 users, we can use three or more machines with Loadgenerator installed in them. The tester will then provide the script and the name of the machine which is going to act as a load generator along with the number of users who are going to run from that machine. LoadRunner uses Monitors to monitor the performance of individual components. But each monitor is to be purchased separately from Mercury. Some monitors include Oracle Monitors, WebSphere Monitors, etc... Once a scenario is set and the run is completed, the result of the scenario can be viewed via the Analysis tool
Analysis This tool takes the completed scenario result and prepares the necessary graphs for the tester to view. The tester can then make needed adjustments to the graph and then can prepare a Loadrunner report. The LR report is mostly in Word format with all the necessary graphs in them. Also, graphs can be merged to get a good picture of the performance.
2 types of recording modes are there in the load runner,URL based and HTML based.
