Interestingly, most businesses realize the enormous benefits of performance testing only when a critical reliability issue hits their production environment. Now, it's no longer a question of what type of application you're developing or what budget you have. Plenty of tools are available—and thanks to the open-source initiative—we can find some effective performance-testing products for free!
Validation of performance requirements must become a fundamental task for every company.
Business teams or functional testers validate their features step-by-step. But is this the way the new application will be used in production? Such testing is bound to be rare cases in which just a single user will use your new or changed application. In reality, hundreds or thousands of users will work most of the time simultaneously. That means your testing does not align with how an application is used post-production.
Here are some new use cases of load and performance testing.
Architecture validation
If we rely too much on whiteboard architectures, we can be in for some big surprises when a new application is deployed to production. The reason for this is two-fold. Firstly, application design is typically a one-time activity during early development. It's difficult to verify whether a developer has followed all the architecture decisions – any minor code changes can severely impact call patterns or data loads. One of the best architecture validation approaches is making it part of your load and performance testing. Then you can simulate production volumes and check how your application stack behaves. Service request volumes, utilization, and transferred data volumes are important figures you should collect before comparing them with the whiteboard-design decisions.
Web-analytics testing
Manually testing web analytics features is not enough. The response times of your applications can have a significant impact on what your web analytics backend captures. For example, imagine your entire revenue forecast relies on web analytics, and due to a slowdown, the analytics integration captures only half of the requests. The decline in revenue that results will leave your C-level managers in a state of shock! Once they discover the trouble was due to an analytics integration that wasn't properly tested, they'll hit the roof! You can avoid such problems entirely by integrating web analytics testing into your performance-testing activities.
Identifying scalability limits
Outages of application servers, web, or database tiers are very hard to avoid. Response times can be affected if your application uses a database deployed on two servers and one of these servers crashes. If your testing approach doesn't consider such scenarios, it's time to close this gap. Then, in the worst-case scenarios, a subset of services and servers will still provide the necessary service to your customers. The resulting slowdowns are often acceptable in such situations, but outages should be avoided at all costs. Performance testing allows you to understand the critical path of your application. Don't miss this opportunity in your performance-testing strategy!
Resilience testing
Applications may work well with only a small number of users. But once the applications have to deal with concurrent-user situations, they gradually fail. Such errors are difficult to catch and require a more advanced approach. This is especially true for financial transactions such as payments, which must be carefully tested for resilience. Once such transactions are safeguarded, the transferred money is refunded, and the intended transaction is canceled. Otherwise, the payment is initiated, but the purchased service is not delivered due to leaking software, and no refund is issued. You can avert such a disaster by combining the failover scenarios with your performance-testing activities to make testing such crucial procedures an everyday activity.
Production simulation
The first day in production should not bring surprises to your operational teams. Ensure you give them enough time to familiarize themselves with the new applications' behavior. Understanding the critical path in such systems is key to the best possible user experience. With IT services becoming more complex, operators need to know which scaling approach has been implemented and the capacity limits within which the applications function well. Involve operational teams in your performance tests and let them see how and when applications break. This experience will help to make them more proactive in avoiding any bottlenecks for new services on production.
Validation of alerting and monitoring
It's the mechanism of how you collect the data that reveals what's going on in your application and which actions you should take based on any changes in your monitoring insights. It's essential to strike the right balance when setting up alerts. Go for the minimum. Otherwise, if your monitoring system is boisterous, you'll risk the warnings being ignored altogether. Performance testing allows you to test your monitoring and alerting systems under real-world conditions.
Where to go from here?
Check out our performance engineering mentor Gobenchmark to get your maturity level and learn how performance engineering could become a fundamental part in your value stream.
Happy performance engineering!