Response time analysis of OPS5 production systems

This paper focuses an the problem of determining a priori the maximal respo nse time of rule-based programs. The response time analysis problem is an i mportant problem, especially for real-time systems. We study this problem i n the context of OPS5 production systems. Two aspects of the response time of a program are investigated, the maximal number of rule firings and the m aximal number of basic comparisons made by the Rete network during the exec ution of the program. The response time analysis problem is in general unde cidable. However, a program terminates in a finite time if the rule trigger ing pattern of this program Satisfies certain conditions. In this paper, we present four such termination conditions for OPS5 production systems. An a lgorithm for computing an upper bound on the number of rule firings is then given. To have a better idea of the time required during execution, we pre sent an algorithm that computes the maximal time required during the match phase in terms of the number of comparisons made by the Rete network. This measurement is sufficient since the match phase consumes about 90 percent o f the execution time.