Scheduling recurring task sets that allow some instances of the tasks to be skipped produces holes in the schedule which are\r\nnonuniformly distributed. Similarly, when the recurring tasks are not strictly periodic but are sporadic, there is extra processor\r\nbandwidth arising because of irregular job arrivals. The additional computation capacity that results from skips or sporadic tasks\r\ncan be reclaimed to service aperiodic task requests efficiently and quickly.We present techniques for improving the response times\r\nof aperiodic tasks by identifying nonuniformly distributed spare capacityââ?¬â?because of skips or sporadic tasksââ?¬â?in the schedule and\r\nadding such extra capacity to the capacity queue of a BASH server. These gaps can account for a significant portion of aperiodic\r\ncapacity, and their reclamation results in considerable improvement to aperiodic response times.We present two schemes: NCLBCBS,\r\nwhich performs well in periodic real-time environments with firm tasks, and NCLB-CUS, which can be deployed when the\r\nbasic task set to schedule is sporadic. Evaluation via simulations and implementation suggests that performance improvements for\r\naperiodic tasks can be obtained with limited additional overhead.
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