If At First You Don't Succeed, Try, Try, Again...? Insights and LLM-informed Tooling for Detecting Retry Bugs in Software Systems

Retry-the re-execution of a task on failure-is a common mechanism to enable resilient software systems. Yet, despite its commonality and long history, retry remains difficult to implement and test. Guided by our study of real-world retry issues, we propose a novel suite of static and dynamic techniques to detect retry problems in software. We find that the ad-hoc nature of retry implementation in software systems poses challenges for traditional program analysis but can be well handled by large language models; we also find that careful repurposing existing unit tests can, along with fault injection, expose various types of retry problems.