Prioritised Petri net is a powerful modelling language that often
constitutes the core of even more expressive modelling languages such as
GSPNs (Generalized Stochastic Petri nets). The saturation state space
traversal algorithm has proved to be efficient for non-prioritised
concurrent models. Previous works showed that priorities may be encoded into
the transition relation, but doing so defeats the main idea of saturation by
spoiling the locality of transitions. This paper presents an extension of
saturation to natively handle priorities by considering the priority-related
enabledness of transitions separately, adopting the idea of constrained
saturation. To encode the highest priority of enabled transitions in every
state we introduce edge-valued interval decision diagrams. We show that in
case of Petri nets, this data structure can be constructed offline.
According to preliminary measurements, the proposed solution scales better
than previously known matrix decision diagram-based approaches, paving the
way towards efficient stochastic analysis of GSPNs and the model checking of
prioritised models
