An Approach to Formally Specifying the Behaviour of Mixed-Criticality Systems

Authors A. Burns, Cliff B. Jones

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Author Details

A. Burns
  • University of York, UK
Cliff B. Jones
  • Newcastle University, Newcastle upon Tyne, UK


The authors acknowledge useful suggestions made by Iain Bate, Sanjoy Baruah and Ian Hayes.

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A. Burns and Cliff B. Jones. An Approach to Formally Specifying the Behaviour of Mixed-Criticality Systems. In 34th Euromicro Conference on Real-Time Systems (ECRTS 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 231, pp. 14:1-14:23, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)


This paper proposes a formal framework for describing the relationship between a criticality-aware scheduler and a set of application tasks that are assigned different criticality levels. The exposition employs a series of examples starting with scheduling simple jobs and then moving on to mixed-criticality robust and resilient tasks. The proposed formalism extends the rely-guarantee approach, which facilitates formal reasoning about the functional behaviour of concurrent systems, to address real-time properties.

Subject Classification

ACM Subject Classification
  • Computer systems organization → Embedded and cyber-physical systems
  • Software and its engineering → Real-time schedulability
  • real-time
  • scheduling
  • mixed criticality
  • rely/guaranteed conditions


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