WCET and Mixed-Criticality: What does Confidence in WCET Estimations Depend Upon?

نویسندگان

  • Sebastian Altmeyer
  • Björn Lisper
  • Claire Maiza
  • Jan Reineke
  • Christine Rochange
چکیده

Mixed-criticality systems integrate components of different criticality. Different criticality levels require different levels of confidence in the correct behavior of a component. One aspect of correctness is timing. Confidence in worst-case execution time (WCET) estimates depends on the process by which they have been obtained. A somewhat naive view is that static WCET analyses determines safe bounds in which we can have absolute confidence, while measurement-based approaches are inherently unreliable. In this paper, we refine this view by exploring sources of doubt in the correctness of both static and measurement-based WCET analysis. 1998 ACM Subject Classification C.3 Computer Systems Organization – Real-Time and Embedded Systems

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تاریخ انتشار 2015