Near-Optimal Fixed Priority Preemptive Scheduling of Offset Free Systems
نویسندگان
چکیده
In this paper, we study the problem of the fixed priority preemptive scheduling of hard real-time tasks. We consider independent tasks, which are characterized by a period, a hard deadline, a computation time, and an offset (the time at which the first request is issued) where the latter can be chosen by the scheduling algorithm. Considering only the synchronous case is very pessimistic for offset free systems, since the synchronous case is the worst case in terms of schedulability. In this paper, we propose a new technique, based on the Audsley’s priority assignment, that reduces significantly the search space of the combinatorial problem consisting in choosing the offsets. In addition, we propose new offset assignment heuristics and show the improvement of combining the new technique and the new heuristics.
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