Runtime Monitoring for Concurrent Systems

Abstract

Most existing specification languages for runtime verification describe the properties of the entire system in a top-down manner, and lack constructs to describe concurrency in the specification directly. \( CSP _E\) is a runtime-monitoring framework based on Hoare’s Communicating Sequential Processes (CSP) that captures concurrency in the specification directly. In this paper, we define the syntax of \( CSP _E\) and its formal semantics. In comparison to quantified event automata (QEA), as an example, \( CSP _E\) describes a specification for a concurrent system in a bottom-up manner, whereas QEA lends itself to a top-down manner. We also present an implementation of \( CSP _E\), which supports full \( CSP _E\) without optimization. When comparing its performance to that of QEA, our implementation of \( CSP _E\) requires slightly more than twice the time required by QEA; we consider this overhead to be acceptable. Finally, we introduce a tool named stracematch, which is developed using \( CSP _E\). It monitors system calls in (Mac) OS X and verifies the usage of file descriptors by a monitored process.