We investigate the nature of the scheduling problem as it arises in critical real-time systems, as well as the nature of its solutions. We establish that critical real-time systems must be designed as fault-tolerant distributed real-time systems. We argue that any provably correct solution to the scheduling problem must rest on on-line algorithms. Limitations of «solutions» currently used or proposed are examined. A design methodology is introduced, which serves the purpose of enforcing the timeliness proof obligation, such proofs being established under incomplete knowledge. Techniques that facilitate such proofs are pointed out and examples of solved problems are given.


Schedule Problem Proof Obligation Earliest Deadline First Operational Scenario Relative Deadline 
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 Berlin Heidelberg 1994

Authors and Affiliations

  • Gérard Le Lann
    • 1
  1. 1.Projet REFLECSINRIALe Chesnay CedexFrance

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