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A Multiframe Model for Real-Time Tasks
October 1997 (vol. 23 no. 10)
pp. 635-645

Abstract—The well-known periodic task model of Liu and Layland [10] assumes a worst-case execution time bound for every task and may be too pessimistic if the worst-case execution time of a task is much longer than the average. In this paper, we give a multiframe real-time task model which allows the execution time of a task to vary from one instance to another by specifying the execution time of a task in terms of a sequence of numbers. We investigate the schedulability problem for this model for the preemptive fixed priority scheduling policy. We show that a significant improvement in the utilization bound can be established in our model.

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Index Terms:
Real-time, task model, scheduling, utilization bound.
Citation:
Aloysius K. Mok, Deji Chen, "A Multiframe Model for Real-Time Tasks," IEEE Transactions on Software Engineering, vol. 23, no. 10, pp. 635-645, Oct. 1997, doi:10.1109/32.637146
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