Modelling systems with dynamic priorities

  • Maciej Koutny
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 609)


In this paper we discuss concurrent systems with dynamic priorities, i.e. we allow the priority relation to change as the system evolves. We identify two classes of such systems, state-controlled and event-controlled priority systems. We define their nonsequential semantics (in terms of step sequences) which reflects both the priority constraints and concurrency specification. It is then shown that for a given prioritised system it is possible to construct an equivalent non-prioritised one. The systems dealt with in this paper are safe Petri nets augmented with a priority specification.


Petri nets priorities step sequence semantics 


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  1. [1]
    Barrett G.: The Semantics of Priority and Fairness in occam. Programming Research Group, Oxford University Computing Laboratory (1990).Google Scholar
  2. [2]
    Beaten J.C.M., Bergstra J.A. and Klop J.W.: Ready-Trace Semantics for Concrete Process Algebra with the Priority Operator. The Computer Journal, Vol. 30(6), 498–506 (1987).Google Scholar
  3. [3]
    Best E. and Koutny M.: Petri Net Semantics of Priority Systems. Theoretical Computer Science 94(1), 141–158 (1992).Google Scholar
  4. [4]
    Bol R.N., Groote J.F.: The meaning of Negative Premises in Transition System Specifications. Report CS-R9054, CWI, Amsterdam (1990).Google Scholar
  5. [5]
    Camilleri J.: An Operational semantics for occam. University of Cambridge, Computing Laboratory Technical report 144 (1988).Google Scholar
  6. [6]
    Camilleri J. and Winskel G.: CCS with Priority Choice. Proceedings of LICS'91 Conference, IEEE Computer Society Press, 246–255 (1991).Google Scholar
  7. [7]
    Cleaveland R. and Hennessy M.: Priorities in Process Algebras. Proceedings of LICS'89 Conference, IEEE Computer Society Press, Edinburgh (1988).Google Scholar
  8. [8]
    Groote J.F.: Private communication (1991).Google Scholar
  9. [9]
    Hack M.: Petri Net Languages. Technical report 159, Laboratory for Computer Science, MIT, Cambridge (1976).Google Scholar
  10. [10]
    Janicki R.: A Formal Semantics for Concurrent Systems with a Priority Relation. Acta Informatica 24, 33–55 (1987).Google Scholar
  11. [11]
    Janicki R. and Koutny M.: Invariants and Paradigms of Concurrency. Proceedings of PARLE'91, Lecture Notes in Computer Science 506, Springer, 59–74 (1991).Google Scholar
  12. [12]
    Janicki R. and Lauer P.E.: Specification and Analysis of Concurrent Systems: The COSY Approach. Springer (to appear).Google Scholar
  13. [13]
    Lamport L.: What It Means for a Concurrent Program to Satisfy a Specification: Why No One Has Specified Priority. 12th ACM Symposium on Principles of Programming Languages, New Orleans, Louisiana, 78–83 (1985).Google Scholar
  14. [14]
    Okulicka F.: On Priority in COSY. Theoretical Computer Science 74, 199–216, (1990).Google Scholar
  15. [15]
    Peterson J.L.: Petri Net Theory and the Modeling of Systems. Prentice Hall (1981).Google Scholar
  16. [16]
    Reisig W.: Petri Nets: An Introduction. Springer (1985).Google Scholar
  17. [17]
    Rozenberg G., Verraedt R.: Subset Languages of Petri Nets. Theoretical Computer Science 26, 301–323 (1983).Google Scholar
  18. [18]
    Salwicki A., Müldner T.: On Algorithmic Properties of Concurrent Programs. Lecture Notes in Computer Science, vol. 125, Springer, 169–197 (1981).Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1992

Authors and Affiliations

  • Maciej Koutny
    • 1
  1. 1.Computing LaboratoryThe University Newcastle upon TyneUK

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