NSF Award
2318953
This project aims to simplify and automate the verification of high-performance distributed systems, i.e., systems that run on multiple computers to improve reliability and/or performance. Such systems are as crucial for our society as they are complex and subtle. This makes them a prime target for formal verification, a technique that can eliminate many classes of bugs from distributed systems. Existing verification approaches, however, are impractical: They require an unreasonable amount of human effort and intuition or rely on unrealistic assumptions about the systems they are verifying. This project will make a number of contributions to bring formal verification closer to practicality, targeting real-world, high-performance implementations, including those that rely on multi-threading. This project will develop Message Invariants, a new way to reason about a distributed system as if it were a centralized system, thus simplifying the human effort and intuition required. It will also explore Ownership Types: Distributed systems often involve concepts of ownership or uniqueness; e.g., when passing a lock around, or when moving keys from one system to another. Currently, such reasoning is done manually—and painstakingly—by the developer. The proposed work will formalize distributed Ownership Types to enable a type checker to quickly and automatically discharge many such obligations, thus simplifying the reasoning for developers.<br/> <br/>The ultimate aim of this project is to make formal verification of distributed systems a practical alternative to the current, best-effort approach of testing, an approach that has fundamental limitations when safeguarding today's large-scale systems from software errors. By automating the verification of real-world, high-performance distributed systems—unfettered by the limitations that come with existing automated approaches—this project aims to ensure that formal verification will not remain an academic curiosity, but will instead be actively adopted by practitioners. A shift from today's best-effort testing techniques to formally verified software will lead to a future where the software products that society depends on will be truly reliable and robust, backed by machine-checked mathematical proofs of correctness. The research program will be complemented by integrated education and outreach initiatives, including an annual summer school and activities focused on broadening participation in computing.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
