With DevOps, Agile, and Lean going strong, the application deliveries appear to be fundamentally different from a few years ago. Developers are more efficient, release cycles are faster, and there are no layers of bureaucracy.
Yet, the testing world finds itself amidst a constant barrage of bugs and product defects. So, where’s the disconnect? And how to fix that?
This article unearths these challenges and presents parallel testing as a unique solution. It can help put testing back to its rightful place as a strategic partner in delivering quality software consistently and reliably.
That said, here’s how the article is structured. Feel free to jump directly to the topic of your interest.
What is Parallel Testing?
How do we define parallel testing? Simply putting in, Parallel testing runs multiple test cases over a set of features or paths simultaneously. It involves testing different application versions with the same input and against a reference environment(s) (such as devices or browsers).
As a comrade to the CI/CD pipeline and legacy to modern system migration, the parallel test ensures that the desired results are achieved, and validations of the product or feature fallbacks are present. As soon as the code is built, parallel testing executes the tests in tandem across multiple platforms. The issue can be fixed and tested for a successful build in case of any defect. This process is repeated until the product is stable enough for release.
How does Parallel Testing Nullify the Testing Challenge?
The sequential style of software testing limits the testing to one iteration at a time, making it a slow process. This is especially true for performance testing, where the tester needs to run multiple test cases within a small-time window. There’s also a high level of dependency within an iteration because sequential software testing requires the outcome of one test to inform subsequent tests.
On the other hand, parallel testing enables testers to run multiple test cases simultaneously. This is very beneficial when changing from legacy software to modern applications. Testers can concurrently test the new software against reference environments (both old and new) to carve out the differences between the output. Such a process saves time and resources while ensuring the stability and success of the product.
How is Parallel Testing Beneficial?
Parallel testing helps identify the root cause of anomalies faster. But, how does this help the business case?
Advocates for broader test scope:
Customarily, teams test any release against a set of configurations and environments. These environments predominantly pertain to the most popular browsers and devices, and understandably so. But, often, it is important to also verify against other variations of the same. For example, if a product is developed on Windows or macOS, it is helpful to test on the equivalent in a Linux environment. Doing so would allow any bugs to surface earlier and quicker and provide opportunities to scale further down the line.
Consumes a fraction of the usual testing time:
The reduction in the time for testing is directly proportional to the number of test cases being concurrently run. And the number of test cases run is a function of the sophistication of the application under consideration. In other words, as the testing scope increases and the segregation of the test cases proliferates, QA teams can test more devices and configurations. This means that the testing time will decrease relative to the test case execution.
Parallel Tests make repetition a boon:
Since the test cycle rapidly iterates and the number of test cases increases, the developer can build a comprehensive regression suite at each release. In turn, this helps increase the chances of identifying abnormal occurrences more frequently and producing more decision-centric data.
Consumes a fraction of the usual testing cost:
Test automation and cloud setup make it possible to reduce the financial and personnel resource expenses. Also ensuring that the product or service stays up-to-date and remains competitive. This will be critical in the forthcoming years when there will be greater demand for modern and scalable products.
Complements the existing testing philosophy:
It is essential to understand that parallel testing works as a supplement to the traditional testing pipeline. Indeed, parallel testing is a better way of doing things; however, it doesn’t necessarily entail tweaking the built-in sequences of the existing software testing process. It is up to the tester to decide whether they want to achieve their organizational value sequentially or in parallel.
Considerations Before Making a Switch to Parallel Testing
Now that we understand the Parallel testing definition, it is also necessary to understand that Parallel testing can be a powerful tool in making iterations more efficient to the point of making them more effective. However, there are some prerequisites to address:
Comprehensive product knowledge is imperative
Familiarity with the product is critical to testing it in parallel. It requires the tester to be highly focused on the product and the rationale behind its development. For example, the interface and design principles. The tester must also be knowledgeable about the specifications for each iteration and the timescales for which a release is allowed to be finalized.
Awareness of the data dependencies
Some tests may rely on different sets of data to test a specific property or function. As long as the tester knows what data to provide for a test, how to get it, and how to mix and match with other data sets provided by other tests, they can proceed with parallel testing.
Parallel Testing broadens the scope and relevance of tests and reduces testing time and cost. It makes it essential that software testers are more familiar with the application under test and can come up with a testing approach that complements the existing testing framework.