Imagine a scenario: you plan an amazing evening for yourself with Netflix, popcorn, and some drink. Yet, when you go to the website, you cannot load any movie. The speed is horrible, the load time exceeds and the entire website crashes. It may seem like not a big deal, but you would most likely feel frustrated.
Let’s look at the situation from the business perspective. Even one inability to watch a movie may cause users’ dissatisfaction and loss of clients. If we are talking, for example, about making a purchase on a website, the business in this case literally loses money when the website crashes, as the revenue of the e-commerce industry directly depends on the performance of the website.
“If an e-commerce site is making $100,000 per day, a one second page delay could potentially cost you $2.5 million in lost sales every year”, Neil Patel and Kissmetrics claim.
The last thing you want for your business is an unexpected crash of the software in the middle of an event that brings many clients. That is why software stress testing exists: it tests extreme conditions, in which the website or a software app cannot operate, to work on ways to handle an extreme load. In this article, we will go over the reasons for a website crash and explain why stress testing is a reliable solution that can save a website and app performance at all times. Being an expert in all types of software testing, we want to share our knowledge and discuss how software testing can help business scale and grow.
Why Does High Traffic Crash Websites?
Understanding the way the e-commerce industry works will give us a better idea on why heavy traffic may crash a website and how exactly it happens. In the modern world, we use websites and make purchases online more than ever before. According to the latest research, the number of digital buyers reached 2.14 billion, which is 27.6% of the entire population.
Now imagine what happens if a well-known blogger recommends a fairly popular product to its audience and leaves a link to a company’s website. If the audience goes directly to the website that is not prepared for an extreme load, it will most likely crash. Or picture that you own an online shop and decide it’s time to scale your business. You invest into advertising, more and more visitors come to your website. Suddenly, the shop crashes as the traffic is way too heavy for it to handle. Considering the money spent on advertisement, the business can lose a fortune.
What makes the website crash? Simply put, it happens when system requests exceed the processing capacity resources of the website. What can we do then? That is when stress testing comes into play. It finds circumstances in which the website or an app cannot handle any additional load, which gives the ability to identify bottlenecks and work on ways to solve the problems.
What is Stress Testing?
Stress testing is one of the performance testing techniques, which defines how well the site or software is dealing well with extreme load conditions. Sometimes, you need to create abnormal conditions and reach a breaking point to see how your solution is handling the load. That’s what stress testing is all about: it puts a heavy load on the website or app to see when it crashes. Stress testing helps to find new ways to enhance the software and make it persistent to sudden changes of traffic.
During stress testing, you would increase the traffic until the website or application fails to operate further. Once the software cannot handle any additional traffic, you could identify how it behaves during the crash and how quickly the system can recover. This way, you can see how to improve performance and discover recovery mechanisms.
Stress testing can easily get confused with performance testing. Even though they may be considered as synonyms, in reality they are different. Let’s add clarity to this topic. Performance testing defines speed, stability, response time, and reliability of software application, while stress testing is one of the performance testing types to analyze the system behavior during sudden traffic spikes. Here are other well-known types of performance testing you can meet:
- Volume testing. This type of software testing focuses on analyzing a software performance under different database volumes.
- Scalability testing. This testing type helps to plan a capacity addition if your system expects to scale up and increase its user load. It is extremely helpful when you want to determine how effectively the application can scale.
- Load testing. During load testing, we examine a capacity software can handle without crashing it, defining an optimal load.
- Stability testing. It measures how the software can function over a long period of time, remaining stable and reliable.
You can find other differences between the above mentioned testing types with practical examples in our comparative article.
How to Perform Stress Testing
Develop a Test Strategy
A strategy is the foundation of any type of testing. During this stage, you gather software data, determine the order of testing activities, and define resources you have. A well-developed test strategy will ensure that your testing efforts will not go to waste and get you results you want to achieve.
Select a Test Tool
Even though you can choose from a variety of tools, we suggest using ones that have gained trust over years or have shown their effectiveness.
- JMeter is written in Java and it is one of the most popular tools in the market, gaining the trust of professionals for over 20 years. It is perfect for situations where you need to measure the effectiveness of the software and see how it behaves, which is crucial for stress testing.
- Locust, on the other hand, is a comparatively new tool, written in Python. You can write scripts in Python only, while event-based implementation allows greater scalability. These reasons are mainly what stole the heart of Locust users. UTOR finds it beneficial for simple documentation, utilization of library requests, Python community support, and a web-server for test results presentation.
Carry Out Testing
When you have a strategy in place and selected tools, you can move on to executing a test strategy. This stage implies creating the stress testing automation scripts and generating the test data for the stress scenarios.
Report Results and Suggest Improvements
This last stage allows you to identify bottlenecks and develop a solution that enhances the software performance.
Here are the metrics you can rely on while performing a stress testing:
Speed
Always ask yourself how fast you can make the website load and find ways to improve its speed. The following metrics can help you:
- Average load times and response times
- Connections per second
- Total network bytes per second and network output queue length
- Garbage collection
Performance
What the website can and cannot handle? Knowing the failure points and bottlenecks allows you to take your solution to a new level. You may check:
- Top wait times for retrieving data from memory
- Bits per second and private bytes
- Memory/disk space/CPU usage
- Amount of latency
Read more: Performance Testing Best Practices: What Teams Ought to Know About Proper QA
Consistency
Your product should remain stable over time and be able to deal with a high traffic load. You can measure the next metrics to define how consistent your system is:
- Page faults per second
- Transactions passed or failed
- Maximum active sessions
- Thread counts and error rate
How to Minimize the Risk of Failure
Below are some tips to help you minimize the risk of a website failure and make sure you have resources to handle a heavy load when you need it the most.
- Use a content distribution network (CDN). You can improve website performance with a CDN. It is a network of servers spread around the globe. As the “nodes” of the CDN are located in various regions, every time users visit the page, the server uses resources from the closest CDN node. This way, users get flawless app performance with a short page load and minimal latency. You can find the difference between high and low latency below:
- Compress images. You can improve the website’s performance and let Google help you by compressing images. Some specialists argue that compression reduces the quality of the image. Yet, there are stress testing techniques and tools you can use to avoid the loss of the image quality (like choosing the right dimension and image format, using informative file names). The easiest way to find balance between quality and size is to use a medium compression and find what quality suits the image.
- Minimize the use of plugins. Another way to help you expedite the website is to minimize the plugins. Too many plugins on the website can affect its performance. Of course, it doesn’t mean you have to delete all your plugins: leaving essential ones will improve the performance of your website without the need for you to give up on helpful instruments. Remove testing, unused, and inactive plugins, then check the effectiveness of the remaining ones.
- Perform software stress testing. While you define the point of failure of your system, you also find new solutions and ideas on how to improve its effectiveness. With stress tests, you monitor a website’s/app’s performance during failures and ensure it has effective recovery mechanisms.
Are you Ready for a Heavy Load?
With stress testing, business owners can rest assured their system can handle even an extreme load when needed. Such testing is a life saver for businesses that expect an increased number of visitors in the nearest future and will have to deal with a sudden change of traffic.
If you feel it is time for your business to scale and you want to be ready for a heavy load, learn more about our load and stress testing services. UTOR ensures your marketing effort and potential sales do not go in vain by testing software for high responsiveness and flexibility. Over the last 5 years, we helped 46+ businesses generate more revenue, eliminate performance bottlenecks, and drive more sales, remaining an expert in different types of software testing.
