Utility-Based Scheduling of \((m,k)\)-Firm Real-Time Task Sets

  • Florian KlugeEmail author
  • Markus Neuerburg
  • Theo Ungerer
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9017)


The concept of a firm real-time task implies the notion of a firm deadline that should not be missed by the jobs of this task. If a deadline miss occurs, the concerned job yields no value to the system. It turns out that for some application domains, this restrictive notion can be relaxed. For example, robust control systems can tolerate that single executions of a control loop miss their deadlines, and still yield an acceptable behaviour. Thus, systems can be developed under more optimistic assumptions, e.g. by allowing overloads. However, care must be taken that deadline misses do not accumulate. This restriction can be expressed by the model of \((m,k)\)-firm real-time tasks that require that within any \(k\) successive jobs at least \(m\) jobs are executed successfully. This paper presents the heuristic utility-based algorithm MKU for scheduling sets of \((m,k)\)-firm real-time tasks. Therefore, MKU uses history-cognisant utility functions. Simulations show that for moderate overloads, MKU achieves a higher schedulability ratio than other schedulers developed for \((m,k)\)-firm real-time tasks.


Schedule Algorithm Robust Control System Overload Situation Target Utilisation Ready List 
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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© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Department of Computer ScienceUniversity of AugsburgAugsburgGermany

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