Non-functional testing: understanding its importance in software development

Rodrigo Carballido

Pincipal Consultant

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Non-functional testing aims to check non-functional aspects of an application, such as performance, usability, accessibility, scalability, etc. It is designed to identify the operational behavior of a system, in accordance with specific functional behaviors.  Therefore, our daily tests are mainly focused on non-functional testing and non-functional requirements.

Increasingly, non-functional testing is becoming more relevant in software development. Currently, our non-functional testing analyzes issues related to security, performance, accessibility, usability, scalability, and other aspects of a software application. These tests have a major impact on applications that support high user traffic, and ensure application stability as well as the ability to support a high number of connected people under extreme circumstances.

The importance of non-functional testing

Lack of testing can lead to software defects that can damage a brand’s reputation, which can generate frustration in customers and increase customer churn rate. In extreme cases, one bug or defect can affect interconnected systems or cause serious problems in the operation.

Car manufacturer Nissan, for example, recalled 1 million vehicles due to a software error in their airbag sensor detectors. Similarly, the launch of a $1.2 billion military satellite was cancelled due to a software bug detection. The numbers speak for themselves. In the United States alone, in 2016, software errors cost the economy $1.1 trillion in resources. Also, they had affected 4,4 billion customers.

While testing itself is quite costly, companies can save millions in development and support each year by applying proper testing techniques and quality control processes. The first software tests reveal problems before a product arrives on the market. The sooner the development team gets feedback from testing, the faster it can solve problems such as:

  • Architectural errors
  • Poor project decision-making
  • Incorrect or invalid functionality
  • Security vulnerabilities
  • Scalability issues
  • Usability issues
  • Differences in visual experiences
  • Poor user experience

The capacity to run tests improves software reliability and applications are delivered with few errors. A system capable of meeting or exceeding customer expectations can increase sales and market share.

Types of non-functional software testing

There are several types of software testing, each with specific goals and strategies, for example:

Load testing: It simulates a certain loading capacity in an application to evaluate its performance. These tests are done with expected demand or at times of low demand. Load testing helps to identify an application’s maximum operating capacity, potential bottlenecks, and identify valleys in performance.

Stress testing: It checks the stability of a system or software application, by applying a load greater than the desired demand to test the operational capacity to a breaking point. This helps to identify breakpoints, peak loads, understanding the safe limits of an application, while determining failure results related to these events.

Endurance testing: It evaluates the capacity of a system or a software application to handle a sustained usage over a significant amount of time.

Scalability testing: It checks the performance of an application by increasing or decrasing the load of, for example, the number of simultaneous users. Systems are expected to increase or reduce in capacity and adjust accordingly to the resources available to ensure adequate and stable performance.

Usability testing: It aims to evaluate the easiness of the customers while using a system or an application to complete a task. Several aspects such as: learning convenience, efficiency, memory allocation, error writing, error recovery, user satisfaction, among others, are evaluated.

Accessibility testing: It is widely used to check if a software application can be used by people with disabilities, or any user facing a situacional disability. These tests verify whether a software is inclusive and can be easily accessed by any user, to improve the easiness of use and user satisfaction.

In each case, understanding these requirements becomes a fundamental assessment in a quality verification process. Equally important, non-funtional testing helps the engineering team to discover difficulties and situations to foresee any software failure.

Even a simple application can undergo a large number and variety of tests. A test management plan helps prioritize the types of testing that provides the most value, based on the time and resources available. Test efficiency is maximized by running the fewest tests to find the greatest number of defects.

Want to know more about non-functional testing?

Non-functional testing follows a common process. Non-functional testing phases include defining the testing environment, runing test cases, writing scripts, analyzing results and sending error reports. Our specialized team will run application tests according to the specificity of each project.

Our experts will answer all your questions!

We are supported by the entire Connectis portfolio, ensuring operational efficiency and the best user experience.

Rodrigo Carballido

Pincipal Consultant

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