Petri net tools for analysis and verification of task scheduling algorithm in real time distributed process control system

This paper first show by formalism that a task scheduling algorithm can be equivalently specified by a set of rules, that is, a set of specification rules can constitute a task scheduling algorithm; and then show that these rules can be translated into a marked Petri net model involving the Petri net place,transitions and arcs that correspond to the states and state transition of the running procedure of the task scheduling algorithm so that reachability graph can be generated in terms of the model. From the reachability graph, we can see if there are livelock, deadlock and other faults of the task scheduling algorithm. In the last part, we illustrate an example to explain the detail process of rules´ equivalent specification, rules´ translation, and reachability graph generation in terms of a task scheduling algorithm, to analyse and verify its correctness and completeness.<>