Black Week is approaching and the planning for discount campaigns in your online shop is in full swing. But what if your shop is literally overflowing and your system can't cope with the onslaught? Early load testing is the key to ensuring that your software and servers shine even when traffic is high. In our blog post, we reveal how you can prepare yourself by choosing the right testing method and become your customers' favourite shop.
The impact of a lack of quality assurance during Black Week
An effective load test is essential for companies before Black Week in order to successfully cope with the massive onslaught of customer traffic. If quality assurance is neglected during this critical time, serious performance issues can occur, resulting in a poor user experience. An isolated server outage or slow loading times can deter potential buyers and significantly reduce sales. It is therefore important to carry out comprehensive tests in advance.
Choose the right time and the right tool for the performance test.
Targeted testing is the key to ensuring that e-commerce systems can cope with the onslaught during BlackWeek without any problems. A performance test helps to identify the load limits of the software and servers before things get serious. The tests can be carried out at various times, both during and after development.
Continuous testing in the development process is recommended. Integration into the CI/CD process is a good practice to continuously monitor application performance. For example, mini-load tests can be integrated into the process to identify performance problems at an early stage. Load tests can also be carried out at the end and shortly before releases. These tests provide a comprehensive check of the entire application under realistic conditions. However, they are also significantly more costly and time-consuming, as system customisations usually require a more complex implementation.
A thorough load test makes it possible to identify and eliminate bottlenecks in the system at an early stage, thus minimising the risk of system failures. In addition, effective load tests not only increase the stability of the platform, but also customer confidence in the brand. Intelligent test automation is an indispensable tool for carrying out regular tests and ensuring high software quality.
By implementing precise load tests one to three months before the discount campaign, the foundation is laid for a smooth process - this is how a shop becomes an e-commerce champion during Black Week.
Now it's time to choose the right tool for load tests, which differ in their approaches to performance testing and the optimisation of cloud applications.
K6, for example, is an open source tool known for its ease of use and integration into CI/CD pipelines. It supports load testing in JavaScript and enables developers to write scalable tests. The advantage of K6 is its flexibility. However, K6 lacks native functions for the automatic optimisation of cloud resources, which makes it less ideal for complex cloud environments.
StormForge, on the other hand, is specifically designed for the optimisation of Kubernetes environments. It offers intelligent resource optimisation through machine learning and thus enables more efficient use of cloud resources. One disadvantage of the Kubernetes focus is for smaller teams.
Choosing the right test environment
Choosing the right test environment is a critical factor when carrying out performance tests, as it significantly influences the validity and reliability of the test results. Different test environments each offer specific advantages and disadvantages that need to be carefully weighed up.
Tests in the development environment can be carried out quickly and cost-effectively, but offer limited validity as they often do not reflect the actual production environment. They are well suited for early tests to identify basic performance problems, but are not representative of later operation under real conditions.
The staging environment is an improved option as it is usually an integrated environment that is closer to the production environment. Here, performance tests can be carried out with prepared test data, which enables a more accurate assessment of system performance. However, this environment requires regular maintenance of the test data in order to make the tests as realistic as possible.
A staging environment, which is a replica of the production environment, offers the advantage of testing under more realistic conditions.
This utilises real data, which leads to a higher accuracy of the test results. This environment makes it possible to identify potential performance problems before they affect the production environment.
Performance testing directly in the production environment provides the most accurate results as it simulates actual conditions. However, this method comes with a high risk of negatively impacting the experience of real users. It should therefore be carried out with great care and under close supervision.
The choice of a suitable test environment therefore depends heavily on the specific requirements and risks that exist in the respective project context. A well thought-out approach can help to optimise system performance and avoid unexpected failures during critical phases such as Black Week.
Determining the appropriate test types
Selecting the right test type is crucial to the success of performance tests, as each test type evaluates specific aspects of the application and infrastructure. These tests should be selected according to the specific requirements of the project.
The test types
Load testing | Is one of the most basic forms of performance testing. It simulates the expected high load conditions to check how the application reacts under them. This type of test is ideal for ensuring that the application remains stable under high user numbers and that there is no significant loss of performance. |
Scalability testing | Goes one step further and checks how well the application scales with increasing or decreasing load conditions. This type of test is particularly important to recognise whether and how the application and the underlying infrastructure react to sudden user increases or decreases and whether they can scale accordingly. |
Capacity testing |
Aims to determine the maximum number of users the application can support before it reaches its performance limits. This helps to understand the load limits of the application and enables capacity expansions to be planned in good time. |
Fault and maintenance load testing | Are designed to test the behaviour of the application under error conditions. This involves checking how the application reacts when errors occur, for example if a server fails or a database connection is interrupted. This is crucial to ensure that the application remains reliable even under unexpected conditions. |
Endurance or stress testing | Tests the application over an extended period of time to identify potential long-term problems such as memory leaks or stability issues. This type of test is particularly valuable to assess the robustness of the application over longer periods of time and to ensure that there are no performance issues that only become visible after hours or days. |
Integration of performance tests into the CI/CD process | Ensures that the performance of the application is continuously monitored. Even minimal load profiles (20-100 virtual users) can be sufficient to recognise and rectify potential performance problems at an early stage. This enables proactive maintenance and optimisation of the application. |
An exemplary process for a load test could look like this: after carrying out capacity tests to determine the nominal load value, a 15 to 30-minute load test is carried out. This provides a detailed insight into the performance of the application under realistic conditions. A key advantage of this is that bottlenecks and weak points can be identified at an early stage. By using appropriate tools, tests can be organised in stages by gradually increasing the load (ramp-up) in order to analyse the application's response to different load levels, typically between 100 and 400 percent of the nominal load.
Common load test errors and how to avoid them
Mistakes in load testing can significantly impact the validity and success of the tests, which is why it is important to recognise potential challenges early on. Thorough planning and careful execution are critical to achieving accurate and actionable results.
- Providing the infrastructure
is one of the first and most important challenges in performance testing. It is crucial that the respective infrastructures are optimally configured to ensure a smooth test process. In the case of external tests, this also includes setting up the necessary access rights at an early stage in order to avoid delays and technical difficulties during the tests. - Documentation of the endpoints to be tested
is another critical aspect. Complete and up-to-date documentation of the API endpoints is essential in order to carry out precise and efficient load tests. Tools such as Swagger can be a valuable aid here by providing a detailed and structured overview of the API endpoints. Complete documentation enables test teams to fully understand the structure and functionality of the API, which in turn facilitates the development of accurate test scenarios. It is important that this documentation is continuously updated to ensure that all changes to the endpoints are captured in a timely manner. This helps to avoid misunderstandings and errors during testing. - Collaboration and communication
between the teams involved are crucial to the success of a load test. To ensure a smooth flow of information, clear communication channels should be established at the beginning of the project. It is also advisable to involve non-technical teams, such as the marketing department, to raise awareness of load testing throughout the organisation. The use of tools such as Slack, Microsoft Teams or email can help to facilitate communication between team members. It is important that everyone involved knows when and how to share relevant information to avoid misunderstandings and delays. Transparent communication promotes mutual understanding and helps to ensure that all teams are on the same page, which ultimately leads to a more successful testing process.
By addressing these challenges early on, the risk of errors during load testing can be significantly reduced, leading to accurate and reliable test results.
Load testing for e-commerce success during Black Week
Well thought-out load testing is essential in order to successfully cope with the huge rush during Black Week. By selecting the right tool, the right test environment and customised test types, realistic loads can be simulated and the performance of a system tested. An effective performance test provides information on how the software reacts under high load so that potential bottlenecks can be identified at an early stage. Targeted load testing allows server and system capacities to be optimised, which is crucial for a smooth shopping experience. If testing is carried out carefully, companies can ensure that their online shops perform even at peak times and offer customers a positive experience.