Abstract
In this paper, we study the problem of scheduling hard real-time periodic tasks. We consider independent tasks which are characterized by a period, a hard deadline and a computation time, but where the offsets may be chosen by the scheduling algorithm. We first show that we can restrict the problem by considering non-equivalent offset assignments. More precisely, we show that there are finitely many non-equivalent offset assignments and we propose a method to reduce significantly this number and consider only the minimal number of non-equivalent offset assignments. We then propose an optimal offset assignment rule which considers only the non-equivalent offset assignments. However the number of combinations remains exponential; for this reason, we also propose a nearly optimal algorithm with a more reasonable time complexity.
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Goossens, J. Scheduling of Offset Free Systems. Real-Time Systems 24, 239–258 (2003). https://doi.org/10.1023/A:1021782503695
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DOI: https://doi.org/10.1023/A:1021782503695