Often a sudden increase in number of concurrent users affect the user experience delivered by a website or web application negatively. As a type of performance testing, load testing helps enterprises to assess the behaviour of web applications under both normal and peak user load conditions. The testers use load testing tools to ensure that the web application does not crash due to peak traffic and stress conditions.
The QA testers have option to choose from several open source and licensed load testing tools. The usage statistics posted on various websites depict that Apache JMeter is currently one of the most widely used performance testing tools. As an open source tool, JMeter helps users to perform load testing without paying any licensing fee. At the same time, it comes with features to accelerate performance and load testing of various software applications.
JMeter has the capability to simulate a group of concurrent users on a single server, multiple servers, and network. Hence, it becomes easier for testers to assess the performance of the application under varying user loads. Also, JMeter send a large number of requests to the targeted server and conveys the statistics information of the web server through test reports and graphical diagrams. It further accelerates performance and load testing by providing an array of useful features.
Why Do QA testers prefer JMeter for Load Testing and Performance Testing:
Cross-Platform and Portable
JMeter is written in Java programming language. The testers can use it just like other pure Java desktop applications. They can even run the performance testing tool on any platform or system that supports Java implementation. Hence, a tester can run JMeter on major platforms like Windows, Linux, and Mac OS. Java makes JMeter both cross-platform and portable.
Evaluates Performance of Various Software
JMeter was initially designed as a performance testing tool for web applications. But the testers can use the latest version of JMeter to assess the performance of different types of applications, servers, and protocols. JMeter accelerates web application testing by supporting HTTP, HTTPS, Java, PHP, ASP.NET, NodeJS and other widely used web technologies. Likewise, the testers can also use the tool to conduct performance testing of SOAP/REST web services and POP3/IMAP/SMTP mails.
Intuitive Graphical User Interface
JMeter simplifies performance testing by providing a robust graphical user interface (GUI). The GUI enables testers to avail two key elements – Test Plan and WorkBench. The users can add the elements required by the JMeter test to Test Plan. Also, they can store the elements along with their corresponding settings in Test Plan. At the same time, the testers can store the test elements temporarily in WorkBench.
Simulates Heavy User Load
JMeter makes it easier for testers to simulate varying user load on a network, single server, or group of server. Hence, the users can evaluate the overall performance of an application precisely under varying user loads. Also, JMeter is designed as multithreading framework. It allows testers to sample many threads simultaneously as well as sample various functions of different thread groups at a time.
Test Report Visualization
JMeter allows testers to generate test result in a number of formats – tables, trees, charts and log files. For instance, a tester can opt for View Results Tree to generate a tree that displays both requests and responses. He even has option to display the responses in various formats – text, HTML, XML and JSON. He can even boost the decision making process by combining graphs and statistical data seamlessly.
Supports Multiple Testing Methods
At present, QA testing professionals widely use JMeter for load testing and performance testing. But JMeter currently supports a number of testing methods including functional testing and distributed testing. For instance, the testers can perform distributed testing seamlessly by installing JMeter and Java on multiple systems and making the server accessible to the tools. They even have option to use a master controller to perform tests on multiple slave systems at a time.
JMeter is designed with an extensible core. The testers can easily enhance the core functionalities of the performance testing tools by using specific plug-ins. For instance, they can use JMeter Plugins at Google Code to avail several new functional extensions and graphs. Likewise, they can use specific third-party plug-ins to avail extra load statistics, provide dynamic input to tests, and facilitate continuous integration (CI).
Despite being an open source performance testing tool, JMeter is supported by an active community. Also, it keeps evolving continuously to accelerate performance testing of varying software applications. Apache JMeter 3.0 came with a redesigned user interface (UI), scripting and debugging enhancements, and improved test report generation feature. The new features and enhancements keep JMeter popular and relevant in the long run.