Car buyers know to research how well a vehicle will perform. They want to be confident that it won't break under pressure and will last through changing environments.
From a software perspective, reliability testing isn't much different. Development teams want to ensure that the code is tested, can handle the load, that the app performs the way it should and scales the way it's supposed to scale.
Let's examine some reliability testing methods and why it can play an integral role in application development.
Why reliability testing?
The shift left movement encourages development teams to devote more attention to important considerations earlier in the dev process. Reliability complements test-driven development (TDD) in the sense that instead of developers creating features that end up not working as planned, they'd instead know that the code was doomed from the start.
Reliability testing is the practice of understanding -- from start to finish -- how an application should handle performance and usage load in any environment. Once the application is up and running, teams can conduct reliability testing in both production and in testing environments. Reliability testing is a constant process of confirming the application can handle anything that's thrown at it -- user load, environment changes, scaling, etc. -- wherever it's running.
Key methods of reliability testing
A good practice to follow in software development is that an application shouldn't be written, modified and updated before it's tested. Instead, software should be tested throughout its entire lifecycle. Or, in the case of test-driven development, you write tests before the actual application code.
The lifecycle means more than just writing the software and testing it. It also means testing the reliability through the DevOps process.
For example, you set up a CI/CD pipeline that deploys software to development, staging and production environments. In a reliability testing environment, the software would be tested throughout the entire CI/CD lifecycle. However, many organizations won't go through this rigorous testing and instead release software to production that doesn't perform the way they expected.
In reliability testing, consider:
- Where can the performance improve? Where can the code be more efficient?
- Predictions around how the application will perform.
- Establish reliability goals (this can change through every environment depending on the app).
Reliability testing tools
When you think about which types of reliability testing tools will fit your organization, you'll likely want to think about the following scenarios that tools on your platform can handle:
- Detect failures and problem points in the application.
- Find performance issues in Day Two operations. With logs, tracing and metrics, reliability testing tells the team what's happening inside an application and how it can be remedied.
- Generate reports and outcomes for each test, which lets developers gather a better understanding of the environment and if the application is performing as it should.
- Regression and feature tests, such as unit tests or mock tests.
If you're using an AI-driven monitoring and/or observability tool, it can alert the team of these problems and potentially solve them.
The goal is to find the mean time to repair (MTTR) and mean time to failure (MTTF).
A few tools that can find these metrics are:
- Apache JMeter (performance testing tool)
- Vegeta (open source performance testing tool)
- Gremlin (Chaos Engineering tool)
Although these tools will mimic the result of reliability testing, the main goal is to ensure that the tool gives you the ability to test performance, simulate performance load and helps you decide whether to fix something after the test.
Who conducts reliability tests?
As reliability testing grows in importance for application development, most organizations have a distinct role on their dev teams dedicated to running and analyzing these tests. Site reliability engineers have become a more prominent position on software and development teams, along with more specialized roles like reliability engineers or platform reliability engineers. Regardless of the actual position's title, their emergence signifies how crucial testing and reliability are for overall application development.