Exact speedup factors for linear-time schedulability tests for fixed-priority preemptive and non-preemptive scheduling

Exact speedup factors for linear-time schedulability tests for fixed-priority preemptive and non-preemptive scheduling

In this paper, we investigate the quality of several linear-time schedulability tests for preemptive and non-preemptive fixed-priority scheduling of uniprocessor systems. The metric used to assess the quality of these tests is the resource augmentation bound commonly known as the processor speedup factor. The speedup factor of a schedulability test corresponds to the smallest factor by which th...

Schedulability Tests for Fixed Priority Scheduling

Tasks can be classi ed as either periodic which execute every some time units or vice versa as aperiodic. Sporadic tasks are a special case of aperiodic tasks which are guaranteed to have a minimum spacing between consecutive instances of the same task. Sporadic tasks sets can be handled by modeling them as periodic tasks and therefore we will concentrate on the former two types of tasks. Sched...

On Fixed Priority Preemptive Scheduling for Imprecise Computation

We present new results in fixed priority scheduling for imprecise computation in real-time systems. Imprecise computation has not been popularized enough for reasons which are rooted from the task model, scheduling methods (EDF-based) and general system support. Audsley et al. have devised schedulability tests for guaranteeing mandatory computation while incorporating unbounded optional compone...

A faster exact schedulability analysis for fixed-priority scheduling

Real-time scheduling for task sets has been studied, and the corresponding schedulability analysis has been developed. Due to the considerable overheads required to precisely analyze the schedulability of a task set (referred to as exact schedulability analysis), the trade-off between precision and efficiency is widely studied. Many efficient but imprecise (i.e., sufficient but not necessary) a...

Preemptive and Non-Preemptive Real-Time Uni-Processor Scheduling