Book Image

Master Apache JMeter - From Load Testing to DevOps

By : Antonio Gomes Rodrigues, Bruno Demion (Milamber), Philippe Mouawad
Book Image

Master Apache JMeter - From Load Testing to DevOps

By: Antonio Gomes Rodrigues, Bruno Demion (Milamber), Philippe Mouawad

Overview of this book

Load tests help identify the maximum number of requests a software system can handle. One popular open source tool for load testing is JMeter. By leveraging the features and capabilities of JMeter, you can perform extensive load testing and fix issues in your application before they become problematic. This book is written by JMeter developers and begins by discussing the whole process, including recording a script, setting it up, and launching it, enabling you to almost immediately start load testing. You'll learn the best practices that you must follow while designing test cases. You'll also explore the different protocols offered by JMeter through various real-world examples. Finally, you'll see how to integrate JMeter into the DevOps approach and create professional reports. You'll discover ways to use the eco-system of JMeter to integrate new protocols, enrich its monitoring, and leverage its power through the use of the cloud. By the end of this book, you'll know all that's needed to perform comprehensive load testing on your applications by using all the best practices and features of JMeter.
Table of Contents (14 chapters)

How Properties Differ from Variables

Properties and variables allow you to make data dynamic in JMeter. So, their purposes are very similar:

  • Variables are tightly bound to their threads, meaning that every thread has its own copy and can manipulate their own version of a variable.
  • Properties are shared among all threads, so changing a property during a test should be avoided. If you really need to change it, ensure that the value is not corrupted by simultaneous access. You can do this by synchronizing this access.

In summary, variables and properties differ in that properties are global and variables are local with respect to threads.

Based on this, we can define two rules:

  • Properties should be used for environment-related data.
  • Variables should be used for user-related data and correlation rules. That's why, for example, extractors in JMeter will create variables.

How Properties Are Created

Properties are created by JMeter, which reads them from: