Integrating Unbounded Software Components into Hard Real-Time Systems

Research output: Chapter in Book/Report/Conference proceedingChapter


The incorporation of unbounded components (i.e. software modules that cannot be analysed to produce realistic worst case execution times) into hard real-time applications has been recognised as a key issue for the next generation of real-time systems. In this paper, we present a system model that caters for the three main approaches to integrating unbounded components: milestone methods, sieve functions and multiple versions. This model is feasible because it is supported by schedulability tests that will guarantee the bounded tasks. These test are defined in the paper. Further, only a simple run-time system that uses pre-emptive priority-based dispatching is required. The wide-spread use of techniques such as imprecise computation will only happen if they are integrated into standard software engineering methods, we therefore also show how the techniques can be realised in Ada 9X
Original languageEnglish
Title of host publicationImprecise and Approximate Computation
EditorsSwaminathan Natarajan
Publication statusPublished - Jun 1995

Publication series

NameThe Springer International Series in Engineering and Computer Science,


  • real-time
  • scheduling
  • fixed priority
  • spare capacity

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