What is Performance Testing?
Performance testing is a series of testing methods employed to understand how a system performs in terms of responsiveness and stability under a specific set of strains. Oftentimes, teams begin performance testing in conjunction with or after functional testing within the test phase of the software development lifecycle.
Why do Teams Performance Test?
Performance testing is an essential means of identifying baselines and bottlenecks to improve scalability, reliability, and resource efficiency. Essentially, it helps teams ensure that every piece of code that is deployed can deliver the experience and functionality they had intended. Over time, teams can track their performance and continue to optimize and scale as they release new updates. Skipping performance testing can cause your websites, applications, and APIs to become slow, have poor usability, and perhaps even lead to downtime in production.
Load testing helps teams understand how their applications will behave under realistic load scenarios. Applying ordinary stress to a software application or IT system to see if it can perform as intended under normal conditions validates that the application is ready to be released and can hold up in production. It is a type of non-functional testing, usually run alongside functional tests.
Stress testing aims to understand what the limits of an application are by applying unrealistic or unlikely load scenarios. Stress testing deliberately induces failures so that you can analyze the risk involved at the breaking points, and then, perhaps, choose to tweak programs to make them break more gracefully. Stress testing is useful for preparing for the unexpected and determining exactly how far a given system can be pushed, exploring the outer limits of performance capacity.
Also known as soak testing, endurance testing keeps the application or system under load for a long duration to see how the app or system degrades over time. Endurance testing is essential to understand and optimize the response times during and after a long period of sustained activity. For example, an application may behave as designed and expected when it’s in use for 2 hours, but after 6 hours, the system begins to fail or behave erratically.
Scalability testing helps understand the application performance when it is scaled up or down in user load or requests. This can refer to the number of users, network usage, number of requests processed, CPU usage, etc. depending on the type of application being tested. Tests can be performed at a hardware, software, or database level to gauge the applications ability to respond to user load changes. Scalability tests are performed to include all levels of load to improve overall scalability of a system.
Spike testing involves suddenly changes in load to identify weaknesses within an application and to see if all aspects of the system can handle sudden bursts in demands on the system. Generally, spike testing an application means testing at extreme increments and decrements.
Volume testing, also referred to as flood testing, aims to reveal how well applications can handle large volumes of data. This type of testing helps teams understand what happens when there's a large amount of data in the database, answering key questions like Does the system respond at the same speed? Is the data stored correctly? Does high volume data affects the speed of processing? Does the system have the necessary memory resources? And so forth.
Selecting a Performance Testing Tool
Finding a tool that can support your team is essential. We know that performance testing practices can take a bit of time in the release cycle, but often they are the indicators for success in production. With performance testing, you can understand how your application is going to perform in production before you deploy, so you can find and fix issues before going live. Testing reveals if your website performs differently under load, whether your code change has unexpected changes, and saves money in the long run by identifying issues before they become costly problems in production. When evaulating a performance testing tool, be sure to keep the following factors in mind:
- Ease of Use - is it easy to create complex, realistic load tests?
- Accuracy - does it run in real browsers?
- Scalability - can you increase or decrease usage/use cases, users, instances?
- Integrations - can you integrate with the tools you use everyday?
Understanding what tool will fit best into your workflows is essential. Luckily, LoadNinja helps teams load test faster without sacrificing accuracy, so teams can continuously release quality software.