A Runtime monitoring tool for actor-based systems

Abstract

This chapter discusses detectEr, an experimental runtime monitoring tool that can be used to formally verify concurrent systems developed in Erlang. Formal correctness properties in detectEr are expressed using a monitorable subset of Hennessy-Milner Logic with recursion, and synthesised into actorbased runtime monitors. Our exposition focusses on how the specification logic is enriched and extended with pattern-matching and conditional constructs which allow monitors to be adept at processing the data obtained dynamically from the system's execution trace. The tool leverages the native tracing functionality provided by the Erlang language platform so as to produce asynchronous monitors that can be instrumented to run alongside the system with minimal effort. To demonstrate how detectEr can be used in practice, this material also provides a hands-on guide that is especially aimed at users wishing to use our tool to monitor Erlang applications.