Efficiency of asynchronous systems, read arcs, and the MUTEX-problem

Two solutions to the MUTEX-problem are compared w.r.t. their temporal eeciency. For this, a formerly developed eeciency testing for asynchronous systems is adapted to Petri nets with so-called read arcs. Furthermore, a com-positional semantics for fair behaviour (in the sense of the progress assumption) is presented. On the one hand, this semantics is related to eeciency testing; on the other hand, it is used to specify formally what a solution to the MUTEX-problem is. It is shown that one of our solutions indeed satisses this speciication and that ordinary nets without read arcs cannot solve the MUTEX-problem.