The Implementation of Mazurkiewicz Traces in POEM

Abstract

Abstract. We present the implementation of the trace theory in a new model checking tool framework, POEM, that has a strong emphasis on Partial Order Methods. A tree structure is used to store trace systems, which allows sharing common prefixes among traces and therefore, reduces memory cost. This structure is easy to extend to incorporate additional features. Two applications are shown in the paper: An extended structure to support an adequate order for Local First Search, and an acceleration of event zone based state space search for timed automata.

Stronger Reduction Criteria for Local First Search

“…We have also built an ambitious prototype implementation of the algorithm that starts to yield results. The prototype uses an implementation of traces and a new adequate order described in [12]. Already for a version of Local First Search according to [1], the results reported here are more conclusive and show that the latter method scales and is a serious partial order reduction method, and although simple often superiour to the one implemented in Spin.…”

A nice labelling for tree-like event structures of degree 3

“…The theory of event structures is presently being applied to automated verification of systems. Some model checkers -see for example [16] and [17] -make explicit use of trace theory and of the theory of partially ordered sets to represent the state space of a concurrent system. The combinatorics of posets is then exploited to achieve an efficient exploration of the global states of concurrent systems [18,19,20].…”