Performance Testing is an integral part of any software or web application today. It is of utmost importance to know if the application will bear the load or crash in different scenarios and on different platforms. And the most outstanding tool used to do so is the JMeter. Here, in this article, you will see everything that is needed to understand JMeter Performance Testing.
What Is Performance Testing?
Performance testing is one of the most critical phases of any product launch to verify and validate the product performance. It refers to testing a program or software under some specific workload and monitoring how it responds. It checks if the application performs as expected under that load, or if it does something unexpected.
It performs performance testing to test the speed, reliability, response time, and resource usage. The goal behind performance testing is to identify and eliminate any potential resistances to the software application.
Performance testing mainly focuses on three factors of a Software Program:
- Speed - If the response of the application is fast or not
- Scalability - The maximum user load is determined
- Stability - The application is checked under varying loads
Why Performance Testing?
Performance testing is used to identify and eliminate the performance bottlenecks in the software application. The testing eliminates performance glitches instead of finding bugs.
Performance testing enables stakeholders to have an idea about the application's stability, scalability, and speed. The testing brings forward the issues that need fixing before the application reaches the market.
Types of Performance Testing
There are six types of performance testing, namely:
1. Load Testing
- Load testing is a type in which it tests an application for its performance at normal and peak usage.
- The performance is checked as per the response time and consistency on different user loads.
2. Volume Testing
- Volume testing is a type where the system's performance is checked concerning the volume of data.
- To perform the test, it enters a vast amount of data into the database.
3. Stress Testing
- Stress testing is a type in which different ways to break the system are found, i.e., how much load a system can sustain.
- It checks how much load a system can hold in an incremental approach.
4. Capacity Testing
- Capacity testing is a type in which it checks an application for its capability to meet business volumes.
- The testing is performed, keeping in mind the prospects of an application and the number of users.
5. Reliability Testing
- Reliability testing is when the application is verified if the application would become normal again after an abnormal state.
- It estimates the time that the system would take to return to its normal state.
6. Scalability Testing
- Scalability testing is a type where the application is determined if it could scale up whenever needed.
- The need for scaling up comes when there is an increase in user load.
Performance Testing Process
The process of performance testing is divided into the following eight parts:
1. Requirement Gathering
- The requirements are identified and gathered from the clients.
- The information on the application’s infrastructure, functionality, and usage is gathered.
2. Selection of Tools
- After the analysis is complete, it performs proof of concept with the available tools.
- The available tools list depends on the tool cost and the technology used.
3. Performance Test Plan
- After the above steps, test planning and designing are done.
- It is the test plan that decides how the performance test will take place.
4. Performance Test Development
- Here, the use cases for the identified functionalities are created.
- Once the clients approve the use case, the script development begins.
- These scripts are then validated, and parallelly the test environment is set up.
5. Performance Test Modeling
- Here the performance load model is created for test execution.
- It is checked if they achieve the performance metrics provided by the clients.
6. Execution of Test
- Initially, the tests are not executed with maximum users that are in the Load model.
- It does the text execution in incremental order.
7. Test Results Analysis
- Results are the most important deliverable for performance testing.
- Here, the ROI and productivity that performance testing may provide are shown.
- At the end of all the steps, it is necessary to have a simplified conclusion
- A brief, descriptive, and to-the-point test report is made.
Performance Testing Metrics
Performance Testing Metric is something that is required to understand the quality and productivity of performance testing.
Several performance testing metrics are used; some of them are:
- Processor Usage: Time spent by the processor to execute non-idle threads.
- Memory use: The available physical memory to process on a system.
- Disk time: It is the time taken by the disk to read or write a request.
- Bandwidth: Bits per second used by a network interface.
- Private bytes: A specific number of bytes allocated to a particular process.
- Committed memory: The amount of virtual memory used.
- Response time: Time between the user’s request and the first response character.
- Throughput: Rate of requests received per second by a network.
- Hit ratios: Number of SQL statements that are handled by cached data.
- Top waits: Monitoring of the wait times that could be cut.
- CPU interrupts per second: Average number of interruptions that a processor receives and processes each second.
- Maximum active sessions: Maximum number of sessions that may stay active at once.
- Thread counts: Determining the well-being of the application by checking the number of running and active threads.
- Disk queue length: Average number of read and write requests that are queued for a sample interview.
- Garbage collection: Returning the memory to the unused system, which helps in monitoring the efficiency.
Tools for Performance Testing
Some of the most popular Performance Testing tools in the market are:
Here, we shall see the most outstanding tool out of these, i.e., the JMeter, and understand what makes JMeter a perfect fit for Performance Testing.
What is JMeter?
The Apache JMeter is an open-source, purely Java-based software. The software is used to perform performance testing, functional testing, and load testing of web applications.
It is used to test load testing functional behavior and measuring performance. JMeter makes it possible by creating a huge number of concurrent users that simulate a heavy load. Initially, JMeter was developed to test applications but now has expanded to other test functions.
To understand why JMeter is the most popular Performance testing tool, let’s have a look at these six reasons:
1. Free of Cost
JMeter is free of cost, has a friendly interface, and allows users to automate their work.
2. Performance Testing of Applications
3. Load Testing and Stress Testing
Performance testing in JMeter includes load testing and stress testing. Hence, it identifies the maximum concurrent users that the server can handle.
The framework in JMeter allows multi-threading, which means several separate thread groups may perform simultaneous and concurrent sampling.
5. Graphical Analysis
JMeter enables the performance testing representation in a graphical format like the graph, tree, table, report, etc., making the analysis representable and interesting.
6. Platform Independent
Since JMeter is entirely Java-based, it can be used across any platform or server to run a Java Virtual Machine.
Demo: JMeter Performance Testing
If you want to learn about downloading and installing JMeter, you can check this video.
Here you will see the process to perform JMeter Performance Testing in 5 steps:
1. Setting up Apache JMeter
- The first step is to go to the Apache JMeter folder
- Go inside the bin folder
- Select the JMeter .bat file
- Double click on this file
This might take a while, and then the JMeter window will open on the screen.
Here, the test plan is renamed as performance testing.
2. Adding a Thread Group
- Right-click on the Performance Testing
- Go to add, then go to Threads (Users) and select Thread Group
Here, the thread group can be understood as users, i.e., the number of users.
It has several options, like
- Action to be taken after there is an error: you can choose it the way you want
- Then, there is a “number of threads” where you can choose the number of users you want
- Then, there is a “ramp-up period in seconds” that states the time gap between the users' hits
- There is a “loop count” option where you can choose how many times the test will run for the number of users. You can also choose the test to run infinite times
- There is also a scheduler here to help you schedule the start time and the test’s end time
- For now, make the number of threads to be 2. And loop count to be 100.
3. Adding HTTP Request
- Right-click on the Thread group, go to add option and go to the sampler option
- In the menu that appears, select the HTTP request option
You can see a Server Name or IP box; it will give the server name or the IP in that.
This demo will use Simplilearn's website, here.
- Go to Simplilearn's website
- Copy the URL from here
- Come back to the JMeter window
- Paste the URL in the Server Name box
Don't give http or HTTPS since these are protocols that will come in the other box and that will be automatically taken in the http request case.
- In the path dialog box, leave a forward slash.
The forward slash is used since the aim is to access the route page.
- Here, this demo will rename this HTTP request as Simple.
Now, to get results, let's add listeners. Listeners are something that is used to provide the outputs of a load test. There are different types of listeners present in JMeter, and a good deal may be added using plugins.
4. Adding Listeners
You can use three different listeners here to have an idea about the representation that the JMeter provides
- Right-click on the Thread Group
- Go to Add, select the Listener option, and go for the view Results in Tree option
- Again, right-click on the listener option and choose graph results
- And for the third listener, right-click again and select the View Results in Table option
Now, it's time to run the test.
5. Running the Test
- Save this JMeter test
- Click the green button and run the test
Now when you visit the "View Results Tree," you can see the test running. Same with graph results. Then you can also see the time the test has been executing.
Since this demo had put two threads and a loop count of 100, the test will run for a while. When you check the "view results in table", you can see different performance testing metrics on the screen. You can see the thread name, label, Sample Time per second, Bytes, Sort Bytes, and the latency.
Then, in the tree option, you can see several performance testing metrics clicking on any of the tests. And in the graph results, you can see the graph coming on the screen now, representing the tests taking place concerning the IP address, thread, and loop counts.
So, what JMeter exactly does is, creates a request and sends it to the server. Once it receives the server's response, it collects them and visualizes those details in a chart or graph. After that, it processes the server's response, and finally, it generates the test results in several formats such as TXT, XML, JSON so that the tester can analyze data.
By now, you would have learned everything about JMeter Performance Testing. You began with learning the basics of Performance Testing and checked its relevance in today's scenario. Then you understood the process of performing Performance Testing and came across different Performance Testing metrics. After that, you saw different tools that can be used to perform performance testing, and one such tool is the JMeter. Here, you learned about JMeter and its needs. Finally, you understood the entire process of Performance Testing in JMeter with a hands-on demo. To learn more about JMeter, check out Simplilearn's Automation Testing Masters course.
If you have any questions for us, do let us know in the comment section below. We will have our experts answer it for you right away.