A Class of Non-preemptive Scheduling Algorithms for Real-time Systems
نویسنده
چکیده
We introduce a class of scheduling algorithms, based upon the estimated extinction time, defined as the latest time a a task must begin its service in order to meet its deadlines in a real time system. At time t the algorithms use a scheduling window which covers the interval [ ( t + g(0), (r + g(t) + ) ], and all tasks with estimated extinction time withiti this window are eligible for selection. The task with the earliest estimated extinction time is selected for execution. The algorithms use an estimate of the gap at the time of completion of all tasks within the window, computed from the current gap, g(t) minus the estimated execution time of tasks withiti the Window to decide whether the system is in a safe state and rejects any new task which would lead to an unsafe state of the system.
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