The Performance Evaluation Tool for Automated Prototyping of Concurrent Cyclic Processes

Abstract

This paper is addressing an issue of distributed systems designing aimed at automated prototyping of Cyclic Concurrent Processes Systems. In such systems concurrent processes compete for access to shared system resources. In order to ensure that a system is deadlock and starvation-free, certain conditions must be satisfied. In this paper, these conditions guarantee that for a given pair (an initial state, a set of dispatching rules) the system - belonging to a specific class - has a steady cyclic state. However, system designers are interested in values of performance indices, such as a rate of resources or processes utilization or the period of the system cycle. Nowadays, the values of performance indices are provided mainly as a result of a simulation process, which requires much more processor power than in case of an analytical method. Thus, in this paper the authors focus on providing a procedure that enables building analytical models of Cyclic Concurrent Processes Systems belonging to a system class considered in the paper. To reach this aim the max-plus algebra formalism is employed. Both the conditions ensuring a cyclic process flow and steps of the procedure are the basis of a software tool, which can be used by designers to prototype systems of desired values of the performance indices. Thanks to the computer program the designers receive a useful tool that helps to validate and allocate distributed control procedures, even in a complex system, which is a composition of simpler systems. The procedure together with the software tool is the main outcome of this paper.