The Top 10 Performance Testing Considerations
Today’s digital consumer has no time for slow, error-prone apps or applications that crash when the load is high. Sadly, there are abundant examples of websites and portals crashing under the weight of heavy traffic. Target, Amazon and other such giants have been subject to crashes that have resulted in the loss of millions on their big sale days. The banking industry too has been subject to these crashes. In recent times, customers of banks such as Barclays, RBS, couldn’t access their banking mobile app since their sites were experiencing major traffic on payday. However, such events can dent the confidence of customers and ultimately have a negative impact on the bottom line. This is why thorough performance testing is essential.
What is Performance Testing?
Performance testing measures validates and verifies the quality attributes of the system such as responsiveness, scalability, stability, and speed under a variety of load conditions and varying workloads. The types of performance testing are:
Load Testing –
Testing to check the system with incrementally increasing load in the form of concurrent users and increasing transactions. Done to assess the behavior of the application under test, till the load reaches its threshold value.
Stress Testing –
Testing to check the stability of the software when hardware resources are not sufficient.
Spike Testing –
Testing to validate performance characteristics when the system under test is subjected to varying workloads and load volumes that are increased repeatedly beyond anticipated production operations for short time periods.
Endurance Testing –
This is a non-functional testing and involves the testing of a system with expected load amounts over long time periods to assess system behavior.
Scalability Testing –
Testing to determine at what peak level the system will stop scaling.
Volume Testing –
This tests the application with a large volume of data to check its efficiency and monitors the application performance under varying database volumes.
While undertaking performance testing, these top 10 considerations need to be kept in mind:
- Test Early And Test Often:
Leaving performance testing as an afterthought is a recipe for testing disaster. Instead of conducting Performance testing late in the development cycle, it should take the agile approach and be iterative throughout the development cycle. This way the performance gaps can be identified faster and earlier in the development cycle.
- Focus On Users Not Just Servers:
Since it is real people that use software applications, it is essential to focus on the users while conducting performance testing along with focusing on the results of servers and clusters running the software. Along with measuring the performance metrics of clustered servers, testing teams should also focus on user interface timings and per-user experience of performance.
- Create Realistic Tests:
Assessing how a software application will respond in a real-world scenario is essential to ensure the success of performance testing. Thus, creating realistic tests that keep variability in mind and taking into consideration the variety of devices and client environments to access the system is essential. Also important is mixing up device and client environment load, varying the environment and data, and ensuring that load simulations do not start from zero.
- Performance is Relative:
Performance might mean something to you and something else to the user. Users are not sitting with a stopwatch to measure load time. What the users want is to get useful data fast and for this, it is essential to include the client processing time when measuring load times.
- Correlating Testing Strategy With Performance Bottlenecks:
In order to be effective in performance testing creating a robust testing environment and gaining an understanding of the users perspective of performance is essential. It is also essential to correlate performance bottlenecks with the code that is creating these problems. Unless this is done problem remediation is difficult.
- Quantifying Performance Metrics:
In order to assess the efficacy of the performance tests, testing teams need to define the right metrics to measure. While performance testing, teams should thus clearly identify:
- The expected response time – Total time taken to send a request and get a response.
- The average latency time.
- The average load time.
- The longest time taken to fulfill a request.
- Estimated error rates.
- The measure of active users at a single given point in time.
- Estimated number of requests that should be handled per second.
- CPU and memory utilization required to process a request.
- Test individual units separately and together :
Considering that applications involve multiple systems such as servers, databases, and services, it is essential to test these units individually and together with varying loads. This will ensure that performance of the application remains unaffected with varying volumes. This also exposes weak links and helps testing teams identify which systems adversely affect the others and into which systems should be further isolated for performance testing.
- Define the Testing Environment:
Doing a comprehensive requirement study, analyzing testing goals and defining the test objectives play a big role in defining the test environment. Along with this, testing teams should also take into consideration logical and physical production architecture, must identify the software, hardware, and network considerations, and compare the test and production environment when defining the testing environment needed.
- Focus on Test Reports:
Test design and test execution are essential components of good performance testing but to understand which tests have been effective, which need to be reprioritized and which ones need to be executed again testing teams must focus on test reports. These reports should be systematically consolidated and analyzed and the test results should be shared, to communicate the results of the application behavior to all the invested stakeholders.
- Monitoring and Alerts:
To ensure continuous peak performance, testing teams have to set up alert notifications that can intimate the right stakeholders if load times fall below normal or in the event of any other issue. This ensures proactive resolution of performance bottlenecks and guarantees good end user experience.
Along with these points, in order to be successful with performance testing, testing teams should utilize the right set of automation tools. These will help in fast-tracking testing initiatives with the least amount of effort, identify the right candidates for automation and create robust and reusable tests to further testing efforts. They should also have a defined troubleshooting plan that includes responses to known performance issues. Finally, testing teams should think outside the box and take into account a broad definition of performance that takes into account factors that users care about, the infrastructure needed to execute realistic tests and look at ways of collaborating with developers to create performance-driven software products. In a performance-driven world – shouldn’t your app have the strength to keep up?