The Ceiling Protocol in Multi-moded Real-Time Systems1

  • Jorge Real
  • Andy Wellings
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1622)


Fixed-priority scheduling has become a very important approach for implementing real-time systems. Two key aspects of the method are its support for resource management using priority inheritance protocols and its ability to model modes of operation. In this paper, we discuss the impact of mode changes on the immediate inheritance priority ceiling protocol. We show that the approach adopted in Ada can result in an increased blocking time for tasks that can unnecessarily jeopardise their schedulability. We propose several solutions to help solve this problem.


Operating Mode Mode Change Priority Assignment Sporadic Task Schedulability Analysis 
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 1999

Authors and Affiliations

  • Jorge Real
    • 1
  • Andy Wellings
    • 2
  1. 1.Dept. de Informática de Sistemas y ComputadoresUniversidad Politécnica de ValenciaSpain
  2. 2.Department of Computer ScienceUniversity of YorkUK

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