Parametric approach to the specification and analysis of real-time scheduling based on ACSR-VP

This paper describes an approach to the specification and analysis of scheduling problems of real-time systems. The method is based on Algebra of Communicating Shared Resources with Value-Passing (ACSR-VP), which is an extension of ACSR, a real-time process algebra, with value-passing capabilities and parameterized processes. ACSR-VP is used to describe an instance of a scheduling problem as a process that has parameters of the problem as free variables. The specification is analyzed by means of a symbolic algorithm, and a boolean expression with free variables is produced as an outcome of the analysis. The solution to a boolean expression identifies under what values of the unknown parameters the system becomes schedulable. The paper presents the theory of ACSR-VP briefly and an example of the period assignment problem for rate-monotonic scheduling. We also explain our current tool implementation effort and plan for incorporating it into the existing toolset, PARAGON.