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Timing Faults and Mixed Criticality Systems

  • Alan Burns
  • Sanjoy Baruah
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6875)

Abstract

Many safety-critical embedded systems are subject to certification requirements. However, only a subset of the functionality of the system may be safety-critical and hence subject to certification; the rest of the functionality is non safety-critical and does not need to be certified, or is certified to a lower level. The resulting mixed criticality system offers challenges both for static analysis and run-time monitoring. This paper is concerned with timing failures and how they can arise and be tolerated. The main causes of these errors are faults in the estimation of worst-case execution times (WCETs). For different levels of criticality, different forms of static analysis for WCET are employed. This give rise to a novel implementation scheme for the fixed priority uniprocessor scheduling of mixed criticality systems. The scheme requires that jobs have their execution times monitored (as is usually the case in high integrity systems). This results in higher levels of schedulability than previously published.

Keywords

Task System Priority Assignment Sporadic Task Relative Deadline Sporadic Task System 
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 2011

Authors and Affiliations

  • Alan Burns
    • 1
  • Sanjoy Baruah
    • 2
  1. 1.The University of YorkUK
  2. 2.The University of North CarolinaUSA

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