Innovations in Systems and Software Engineering

, Volume 5, Issue 3, pp 163–179 | Cite as

Verification of real-time systems with preemption: negative and positive results

  • Frédéric Boniol
  • Jérôme ErmontEmail author
  • Claire Pagetti


The aim of this article is to explore the problem of verification of preemptible real-time systems, i.e. systems composed of tasks which can be suspended and resumed by an on-line scheduler. The first contribution of the article is to show that this problem is unfortunately undecidable. To overcome this negative result, we restrict the real-time tasks to be periodic and the implementation to be functionally deterministic, meaning that the preemptions do not affect the functional behaviour and preserve some temporal properties satisfied by the specification. We prove that the verification problem of functional determinism is decidable. This outlines a verification strategy: (1) prove that the scheduled real-time system is deterministic, (2) consider a deterministic non preemptible behaviour which is functionally equivalent to the executions and (3) verify the properties on this behaviour.


Schedule Policy Earliest Deadline First Hybrid Automaton Preemptive Schedule Counter Machine 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag London Limited 2009

Authors and Affiliations

  • Frédéric Boniol
    • 2
  • Jérôme Ermont
    • 1
    Email author
  • Claire Pagetti
    • 1
    • 2
  1. 1.IRIT-ENSEEIHTCamichel, ToulouseFrance
  2. 2.ONERA-CERTBelin, ToulouseFrance

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