Software performance testing is vital for determining how a system will perform under various loads and conditions. Performance testing does not seek to identify defects or bugs but instead measures performance in relation to benchmarks and standards. It helps developers identify and diagnose bottlenecks. Once bottlenecks are identified and mitigated, it’s possible to increase performance.
Performance testing differs from functional testing, which focuses on individual functions of the software. This includes interface testing, sanity testing, and unit testing. More or less, testers check to ensure that functions are carried out properly and serve their purpose.
Performance testing, on the other hand, tests the readiness and overall performance of the software and the hardware it runs on. As such, performance testing is typically conducted after functional testing.
Ultimately, poor performance can drive users and customers away. In its turn, sound performance testing will help you identify areas for improvement.
5 Essential Aspects of Performance Testing
It’s important to identify and test several performance aspects of the software under load. Doing so will help you detect bottlenecks and other potential issues. Let’s examine five of the most commonly tested metrics.
Load Testing: it examines how a system performs as the workload increases. Workload can refer to the volume of conducted transactions or concurrent users under normal working conditions. Load testing also measures response time.
Soak Testing: also known as endurance testing, soak testing is an assessment of how the software performs over an extended period of time under a normal workload. This test is used to identify system problems, such as issues with database resource utilization or log file handles.
Scalability Testing: it tests software performance under gradual increases in workloads, or changes in resources, such as memory, under a stable workload.
Stress Testing: it measures how a system will perform outside of normal working conditions. For example, how will the system respond when faced with more transactions or concurrent users than intended? This helps to measure its stability and enable developers to identify a breaking point. Stress testing also allows developers to see how the software recovers from failure.
Spike Testing: this is a specific type of stress testing that demonstrates the software response when this software is repeatedly hit with large, quick increases in load.
Performance Testing Step by Step
Most of your time is going to be spent planning the test rather than running it. Once you run the test, most of the work is handled by the hardware. Of course, after results are generated, you’ll have to analyze the output. Now let’s examine the performance testing process step by step.
Identify the Test Environment
To get started, you’ll need to identify the physical test environment, including hardware and network configurations. You’ll also need to have the software set up. By understanding the test environment and matching it as closely as possible to real-world conditions, the test itself will be more accurate and provide better insights.
Know Your Performance Acceptance Criteria
You should know what goals you want to reach. This means determining the acceptable levels of response time, resource utilization, and throughput. Also, consider various configurations that could affect performance.
Plan and Design Tests to Identify Key Scenarios
Next, you need to identify key scenarios based on the anticipated real-world use. Different users will generate different demands. It’s important to account for as many of them as possible by determining variability among representative users. Once variability is determined, it’s important to simulate the conditions and to test the performance correspondingly.
Configure the Test Environment
Now it’s time to revisit the test environment and to set up the monitoring structure. This step will be highly dependent on your software, hardware, and other factors. Review your work to make sure there are no errors.
Execute the Test and Gather Data
Once the test is set up, it’s up to your hardware and software to carry it out. Make sure you gather data and closely observe the test as it unfolds.
Digest the Results
In a sense, the real work doesn’t begin until the performance test is completed. Once you’ve gathered data, you’ll need to analyze the results. Pay attention to bottlenecks, critical failures and any abnormalities. Also, run the test again to ensure that performance is consistent.
Some Best Practices to Keep in Mind
When setting up your test environment, you need to consider how your software will perform in the real world. Take into account the variety of devices and client environments, such as different web browsers, that will be used to access your software. Also, don’t start your test from the boot-up as most people will be using your platform while it is already under load.
Further, set a baseline for user experience. Performance data is vital. However, the most important question is “how satisfied are the users?” Understand how decreasing performance will detrimentally impact them.
Conclusion: Be Ready to Start Over
Once the first round of the test is completed, you’ll be able to identify potential bottlenecks and other issues. These problems should be addressed. This may mean changing hardware or rewriting code, among other things.
However, every time something is changed, it’s important to conduct another performance test to see if results have improved. By doing so, it’s possible to incrementally improve and maximize the performance of the software and corresponding hardware.