How to Prepare for Peak Sales with Testing

Every year, Black Friday turns into a survival test for online retailers. This is a time not only of record sales, but also of significant peak loads on website infrastructure. In October and November, traffic to e-commerce platforms increases several times, and those who are not properly prepared face serious risks – from failures and website crashes to loss of revenue and customer loyalty. That is why testing websites for resistance to peak loads becomes not just a technical task, but a critical step for successfully passing the sales season. Without proper preparation, the likelihood of downtime and financial losses increases significantly, which is why investments in testing become economically justified.

According to Akamai, 49% of visitors expect a site to load within two seconds, and another 30% within a second. If it doesn't, 50% will leave for another site, and 22% will never return.

That is why, during sales periods, when sellers fulfill and exceed sales plans, losses from insufficient testing of large retail platforms amount to billions of dollars.

How to prepare?

When preparing for peak loads, especially during events like Black Friday, performance testing plays a key role. Functional testing is important for the overall correctness of the software, but it is load testing that allows you to assess how prepared the system is for a sharp increase in traffic. It is important to choose proven and high-quality platforms for load testing to ensure the stability and sustainability of your site under conditions of intense demand. Without such preparation, the site can slow down or even fail at a critical moment. Experts from Performance Lab, one of the market leaders in the field of load testing, share best practices for preparing for sales with readers of Global CIO.

Load Testing – Can Your System Handle the Influx of Users?

In real life, an online retailer may face a situation where instead of a few hundred visitors, the site receives 3, 5, or even 10 times more users than usual. Without proper testing, this will lead to crashes, slowdowns, or complete inaccessibility of the site.

The main stages of load testing:

1. Creating a test environment. Performance testing on a real site is not recommended, but in some cases it may be justified. For example, if it is impossible to create a full copy of production, testing in technical windows with minimal user load is allowed. If testing is carried out on a separate environment, it must be completely identical to production – from server configuration to traffic volume.

2. Modeling user behavior scenarios. Analyzing your website statistics will help you model real user behavior. Create a load profile that reflects the actions of real buyers: how many of them simply browse products, how many go to the shopping cart, how many place orders. For example, 20% of users go to the catalog, 10% use search, 5% place orders. Such a scenario will help you see the real picture under load.

3. Different types of loads. Don't limit yourself to testing under normal load. Scenarios should include peak, stress, and sustained loads. For example, test what happens if traffic doubles for a few minutes. The system may work fine under normal load, but freeze or become slow to respond under peak traffic.

4. Monitoring during tests. Pay attention to such indicators as page response time, processor load, memory and disk subsystem usage. If the response time increases from 3 to 11 seconds as the load increases, this means that the site cannot cope with the influx of users. Your task is to identify and eliminate “bottlenecks” before the sale begins.

5. Optimize frontend speed. According to Google, 53% of users abandon mobile sites if they take more than 3 seconds to load. Even if the backend can handle the load, the browser may still need time to render pages. Tools like Google PageSpeed ​​Insights, Pingdom, GTmetrix, and WebPageTest.org can help you identify which elements are slowing down your frontend. It’s also important to consider aspects like user geolocation and the network connections used in testing. If your site scores less than 90 on PageSpeed, users are likely to experience page loading issues.

"For accurate modeling, it is necessary to create software scenarios of their actions and use special tools to simulate high load. It is almost impossible to conduct such testing on your own, without experience and suitable tools. Companies often decide to conduct professional performance testing to ensure stability not only on Black Friday, but also in the long term ," explains Vladimir Kashirsky, CEO of Performance Lab.

Recommendations for preparing for load testing

To successfully conduct load testing, it is important not only to create a test environment that is as close as possible to the production environment, including server configuration, data volume, and traffic level, but also to consider nuances related to security systems and partner services. If a site uses CAPTCHA, it must be disabled for the duration of testing, especially if the load is applied to a "production" environment. Similarly, AntiDDoS systems, whether production or a dedicated environment, can block increased load coming from one or more IP addresses. To avoid this, you should add the IPs used to the whitelist of the AntiDDoS service for the testing period.

When testing requires checking user registration, there is no need to use a pool of real phone numbers. It is enough to temporarily disable SMS verification if the site uses two-factor authentication. In cases where functionality is tested within the authorization zone, a data pool will be required, including logins and passwords for test users, which will ensure completeness of scenario testing.

Additionally, if testing is performed on a third-party provider’s infrastructure or involves partner services, it is important to coordinate time windows and test conditions with them in advance to avoid access restrictions. Incorporating these measures into the testing process will ensure that you get the accurate and reliable results you need to successfully launch the system under real-world load.

Automate steps to prepare and conduct load testing. Speed ​​up processes quickly and on a budget

Automated performance testing solutions can significantly speed up the process of preparing a website for high loads. These tools help simulate the work of a large number of users, automate complex behavior scenarios, and provide detailed reports. An example is the Boomq platform. It is useful for those who do not have their own team of developers and testers, but need to ensure stable operation of the site under high load conditions in a short time and with a small budget.

Testing platforms typically offer:

1. Automatic creation of a load profile for static website pages based on data from Google Analytics.

2. Fast execution of tests with a large number of virtual users.

3. Simulating various scenarios of behavior on the site, such as mass ordering.

4. Analyze site performance and identify potential problem areas.

"We use the platform when clients want to make the testing process in teams simple and transparent. Each team member can see the actions of other users: whether the test is currently running, what is the status of the last test and what are the results. Flexible configuration of the role model allows us to make the testing process transparent for all interested participants. This platform allows us to optimize the time spent on systematic analysis of testing results thanks to built-in test comparison dashboards, automatically generated express reports and trend reports. Tracking changes in the performance of a site or application in the dynamics of several releases becomes simple and convenient," comments Boris Seleznev, Product Manager Boomq.

Functional testing: does everything work as expected?

Functional testing is the basis for ensuring the correct operation of the site under conditions of normal and increased user activity. When the number of visitors increases several times, even minor bugs can become a reason for users to refuse further interaction with your site. If the interface elements do not work correctly, the registration system "crashes", and the order processing is delayed, you risk not only losing income, but also customer trust.

What to check first:

1. User scenarios. "We recommend testing the user's entire path from registration to order placement. Errors can appear in the most unexpected places: a problem with the "pay" button or an incorrect delivery calculation – and the buyer will go to competitors," comments Vladimir Kashirsky, CEO of Performance Lab.

Example scenarios to test:

• Registration, authorization, password recovery.
• Search and filter products.
• Adding products to the cart and ensuring they are displayed correctly.
• Placing an order, choosing delivery, payment.

2. Cross-browser compatibility and adaptability. “Check the site’s performance in different browsers (Chrome, Safari, Firefox, and IE) and on different devices – from desktop PCs to mobile. Often, small bugs or slow loading in mobile versions become “silent killers” of conversions. For example, slow JavaScript can significantly slow down page loading, especially on mobile devices, which is critical in the context of mass sales,” explains Boris Seleznev, Product Manager Boomq at Performance Lab.

3. Checking the correctness of payment systems. It is important to make sure that all payment methods function without errors. Any failure in the operation of payment systems is a loss of money and reputation.

During sales, the quality of the IT team's work becomes critical and you have no right to make a mistake. Your preparation for peak loads directly affects the company's final financial indicators. As practice shows, businesses that invest in high-quality testing benefit from stable website operation and customer retention.