Loadrunner- A performance Testing tool

Folks! I know I am not good in writing blogs and since it’s my very first day in this pursuit, you can expect some unexpected omissions/mistakes. :)

So let me begin with the introduction to web performance testing tool- Loadrunner.


Introduction:


Loadrunner was developed by Mercury and has been one of its extensively used kind of tool for the performance testing of various applications on different protocols (like- HTTP, SAP, Oracle, Seibel, SOAP, ICA to name a few) . I am not aware of much about the history of LR (Commonly used term for Loadrunner) but as per my tiny knowledge base, it came in the market with version 7.01 in August 2001. Later on many other versions came in the market but not with full fledged stable functionality. So Loadrunner was emerged with one of its stable version - v8.0. Currently the latest version which is being used in the IT era are version 9.0 and 9.5. Although version 9.0 has got few or for some several bugs. About version 9.5- this is now under functionality of user and so far there are positive outcomes to go with.


To give LR a shot one can start with an evaluation version of 10 days which can be downloaded from http://www.hp.com/ Ohh!!! I forgot to mention that Loadrunner is now with Hewlet Packard (HP). Mercury was acquired by HP on 25 July 2006 and on papers all the acquisitions were completed on 6 November 2006.



Components Of Loadrunner

There are four components of LR-

1) VUGen (also called as Virtual User Generator)

2) Load Generator (Also called as Load Injector)

3) Load Controller

4) Load Analyzer

First Component- VUGen

VUGen component is used primarily for recording the script. Then one can customize (modify) the script. I will be completely describing on how to record the script and how to customize in the later part.

Second Component- Load Generator

The significance/ function of Load generator(s) is/are first these are agents (clients) used to send the request to the web server and second, it communicates with the Load Controller (discussed in the next section).

Third Component- Load Controller

The third component is Load Controller which is used for the management of scripts/scenario/scheduling/monitoring/request/responses etc.

This is the platform on which a tester includes the scripts to be executed and configures the timing for how long the test will continue- Start time, end time, ramp-up, ramp-down of users etc...

Also, it allows tester to add the measurements for various performance counters for analyzing the resource usage of various servers (like Web server, App server, DB server, Report server etc)

Fourth Component- Load Analyzer

Load Analyzer is the tool used for analyzing the result of the performance/load test. This is very interesting area where an analyzer requires very good analytical mind. This tool provides you all kind of graphs like- transaction response time, running virtual users, error graphs, resource utilization graphs etc..

Moreover, you can create the template(s) for reusability, you can filter the un-necessary information from the result, you can save the session and generate the reports in various formats like- excel, word and HTML.