With the festive season fast approaching, many businesses anticipate an increase in traffic to their websites. Whether it’s for holiday shopping, special promotions, or simply the general hustle and bustle of the season, the spike in visitors can put your website to the test. But the real question is: is your website capable of handling the surge? Now is the perfect time to perform load testing and make sure your site can withstand the traffic without compromising performance.
What are the risks of a busy website?
Having a bustling website is usually a sign of success, but there can be unintended consequences if your infrastructure isn't prepared to handle the traffic. One key issue is server performance - when your site experiences high demand but lacks adequate server resources, it can slow down or even crash, leaving customers frustrated.
Did you know that server performance also impacts your SEO ranking? Google’s algorithms take into account how quickly a website becomes usable to users. This metric, known as First Contentful Paint (FCP) or Time to Interactive (TTI), can suffer if your server is struggling to keep up with demand. In fact, a slow website can negatively affect both customer experience and your search engine rankings. This is why it’s crucial to test your website to ensure that, even under heavy loads, it continues to deliver a fast and seamless experience. As we wrote about in September’s blog post about page performance, a slow website at any time of year affects a customer’s perception of your brand – being less likely to return or recommend to friends or family. At a busy time of year, when order values increase, and customers are even more pressed for time, adding frustration to their experience isn’t going to be welcome.
How does load testing help websites serve high traffic?
Load testing is a performance testing technique used to evaluate how a system performs under expected or unexpected traffic conditions. It involves simulating a specific number of users or transactions to see how well the website or application handles the load. The primary goal of load testing is to identify potential bottlenecks or performance issues—such as slow response times, server crashes, or excessive error rates—that may arise when traffic increases. Key metrics to monitor include:
- Response time: How long it takes for the server to respond to a user’s request.
- Throughput: The number of requests the system can process within a certain timeframe.
- Concurrent virtual users: The number of virtual users making requests at the same time.
- Error rates: The percentage of failed requests during the test.
- Resource utilization: CPU, memory, bandwidth, etc.
Load testing can give website owners confidence that their server architecture and website or application can handle the anticipated traffic without negatively impacting performance or customer experience.
How do we load test a website?
It is impossible to suitably load test a website manually – the amount of traffic needed to test the limits of server infrastructure will likely be in the hundreds of requests per second. That means we need to rely on tools and automation.
There are numerous tools available for load testing, each suited to different environments, programming languages, and requirements. Many of these tools are open-source and community-supported, meaning you have access to a wealth of resources, tutorials, and troubleshooting advice.
Load testing often needs two elements: the test and load generators.
There are many open-source tools available that allow developers to design their tests. At Logic+Magic, when designing load tests for clients, we’ve primarily used JMeter an open-source solution developed by The Apache Foundation. Though not a visually stunning experience, it’s had decades of development behind it, has a fantastic support community and is incredibly portable.
We’ve also been looking at Gatling, another open-source library that's easy to configure and run. We like the look of Gatling as it includes a JavaScript SDK that would improve the developer experience and can be integrated into a CI/CD pipeline for continuous testing.
Gatling provides access to a cloud load generating tool and we’ve also had a good experience with https://www.blazemeter.com/ and https://www.tricentis.com/products/performance-testing-neoload. Each of these providers use cloud computing to spin up servers that provide the processing power needed to generate hundreds, thousands or even more virtual users as the test subjects.
Data from these threads of users are recorded and fed back in easy-to-read dashboards covering all the key metrics.
Regardless of the tooling used, the aim of the test is to generate realistic traffic patterns to mimic how real users navigate through the site. It would be easy to write a test for a single user journey who arrives on the homepage, selects a single product, and checks out within 10 seconds. This might give you some idea of performance, but it won’t show all the bottlenecks.
Our method takes a more analytical approach to the design of the test. We take time to understand how real users journey through the website. We use data from server logs and site analytics to create a more realistic test, understanding that different users will take different steps to arrive at the same result.
Imagine we’re testing an e-commerce store. An ideal test would include different entry points, loading different products and a different number of them, performing keyword searches with realistic search terms and pausing between each request to show customers taking the time to read page content before completing their journey.
Analysing the results of a test like this is far more likely to show where customers experience performance issues, or the server hits its limits.
Understanding the ceiling of your website or hosting capabilities means you can then make decisions if the headroom between that and your expected traffic will be enough for everyone to experience a trouble-free experience.
Why load testing matters now
As we head into the holiday season, the last thing you want is for your website to be unprepared for the surge in visitors. Load testing gives you the peace of mind that your site will perform smoothly under pressure, and it helps ensure that your SEO rankings, customer experience, and bottom line don’t suffer because of poor performance. If you haven't conducted load testing yet, now is the time to act.
So, with the festive season on the horizon, don't wait for performance issues to catch you by surprise. Make sure your website is ready to handle the influx of visitors and always deliver an exceptional customer experience.
Software Services Director
