Updated March 28, 2023
Introduction to JMeter load testing
With the current situation where “Time is money,” and in the age of the digital world, the website is judged on the basis of how quickly they can respond a user experience needs to be seamless because any delays in the responses in a webpage might lead to distraction to users attention and hence leading to lesser revenue generation, the purpose of building the website. Research says that a 1-sec delay might result in 7% lesser conversions and 16% of lesser customer satisfaction. So, do we get the point where it is all about milliseconds we are talking about in today’s time and maybe nanoseconds sometimes? So here is where we would take help from JMeter to lessen this delay as less as possible. In this topic, we are going to learn about JMeter load testing.
Explain the JMeter load testing
In our previous discussion, let us just do the math. In case our website earns $1,000 per day, a loss of 7% will result in a loss of $25,500 just because of this 1-second lag. Just think about this loss if our site earns 1 million per day. Before we learn about JMeter and about its load testing, let us first look into performance testing, of which load testing is one aspect. Load testing is to make sure that our website will be performing in the same way and at the same speed even if it is put under heavy load, obviously as per the standards of the industry, and should not break!
This test will also help us understand the maximum requests the software system we are trying to test can handle. This is because we try to replicate an environment that simulates how a user responds in the real world in this testing scenario. This replication of human behavior is sent through as different API calls, maybe a lot of concurrent requests. One this testing process has been carried out, it will eventually open up the bottleneck, which will slowly start degrading the performance. And once this bottleneck is identified, the software development team can work on optimizing that and eventually result in the best user experience.
JMeter is built of different elements, and each element has its own purpose of getting built. In the following paragraph, we would like to understand these elements and get the purpose of their build. So, to start off, the first one is the Thread group. This element simulates how many users are present, and each thread resembles a user. For example, if you set threads to 100, JMeter will automatically create and simulate an environment with 100 users. The next element in line is Samplers. Samplers are nothing but a helping tool in making the thread group understand what type of request is to be made. Requests like FTP, HTP, JDBC are supported, and this is what samplers help in differentiating to the threads. The third is listeners, and as the name suggests, it “listens” to the response and then shows the result of the test execution in the form of either tree, graph, or any other supporting output format. The last but essentially the most important is the configuration element. For later use, this element sets up default so that running another set of load testing is not again a heavy task as the first time!
Let us jump into the steps of JMeter load testing next.
How does JMeter load testing Work?
In our previous section, we have gone in-depth about the elements of JMeter, and in this section, we would go ahead with the steps which are a part of JMeter load testing and will get an essence of how JMeter works.
The first part of JMeter load testing is building a test plan. In the test plan, we list the sequence of steps that need to be carried out, and this plan will the blueprint of how the load test will be simulated. The next part of the load testing is running the basic test plan. Now that we have our plan set up, we would be running the test to get the results, visible in the View results table in the left pane of the tool. Each of the samples will be run, and the status of each would be reported here. The last part is about increasing the load. We would slowly start increasing the load, let’s say with 10 threads over 10 seconds and go all the way, let’s say hypothetically, to 100 threads over 10 seconds. With each delta increase in the thread, we would be able to judge the performance and might get into a position to visualize a point where we would start experiencing performance degradation.
In a nutshell, in JMeter, the request is created and sent to the server. Then the responses are processed from the server and then are collected, recorded, and visualized. Finally, the test results are generated, available in different formats like text, XML, JSON, etc.
Importance of JMeter load testing
JMeter comes into the software industry as a boon in filling out many void spaces, which were still open before JMeter was introduced. Let us discuss these wide spaces so that one is aware of the importance JMeter brings in, in the life of a tester.
- Making a test plan was never easy! There were hundreds of elements scattered here and there, and incase not properly looked through, it would lead to missing out on some test cases. JMeter brings in a comprehensive GUI with a drag and drop facility so that the available list of testing options is available right in front of your eyes, and nothing is missed out. Add what you need all just by a right-click!
- This tool helps not only in load/performance testing but also helps in performing other non-functional testing like stress testing, web service testing, etc. So, it is an all-in-one tool for testers, and this would allow them to no look anywhere else.
- To mimic user behavior, it is essential to record the user’s activities, and this is where JMeter can record the actions, using a Proxy Server, when a user browses in the normal web browser.
- And not to forget, JMeter helps in database server performance evaluation as well and supports protocols like JDBC, LDAP, SOAP, etc.
Using JMeter, one can plan for loads of important activities which will be aimed at improving the server setup, bottleneck reduction, and performance enhancements. The simulation which JMeter uses actually mimics what 100 users would be doing concurrently and thus helps in the overhead reduction in arranging for actual 100 users to test. Just think about the amount of money we can save by increasing the performance of our website just by a second. All the great work of the website will bring its true colors when load tested and performs at par with any other competitive site!
This is a guide to JMeter load testing. Here we discuss How does JMeter load testing Work along with the explanation and importance. You may also have a look at the following articles to learn more –