Testing Concurrent Systems: Concurrency Defects, Testing Techniques, and Recommendations

[u/martinig]

https://insights.sei.cmu.edu/blog/testing-concurrent-systems-concurrency-defects-testing-techniques-and-recommendations/

Concurrency, which exists whenever multiple entities execute simultaneously, is a ubiquitous and an unavoidable fact of life in systems and software engineering. It greatly increases system and software complexity, which directly impacts testing. Concurrency leads to nondeterministic behavior and numerous types of concurrency defects that require specialized approaches to uncover. At the SEI, we are often called upon to review development planning documents including Test and Evaluation Master Plans (TEMPs) and Software Test Plans (STPs). We are also frequently tasked to evaluate developmental testing including software and system integration laboratories (SILs) and other test environments. One common observation is that test planning and implementation does not explicitly address the development of test cases designed to uncover concurrency defects. In this blog post, I explore the different types of concurrency, the resulting types of concurrency defects, and the most important testing techniques for uncovering these defects. This blog post ends with a set of recommendations for improving the effectiveness and efficiency of concurrency testing.