Timing analysis of reactive rule-based programs

Abstract

Predictability is the crucial feature of real-time systems. It requires that all the tasks in a system meet their timing constraints. For an embedded complex system involving a number of subsystems, the timing properties of the subsystems play an important role, since the total system’s response depends on the temporal behaviour of all the subsystems. In this paper, the timing properties of reactive programs written in a rule-based language R L are analyzed. R L is a relatively simple rule language for programming the discrete part of hybrid applications, implemented using a layered architecture. The language has already been used in prototyping a complex automotive application. The upper timing bounds for R L programs, executed using either of the two evaluation strategies, have been studied. Moreover, an analysis tool has been implemented and applied to derive the timing behaviour of a non-trivial application. Some comments on the temporal behaviour of a layered system, consisting of a discrete R L program combined with a set of periodic tasks, are given.