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...ruah}@cs.unc.edu each sporadic task, and all the jobs generated by a task are assigned the priority of this task. Examples of staticpriority scheduling algorithms include the rate-monotonic algorithm =-=[11]-=-, in which higher priorities are assigned to tasks with smaller values of the period parameter, and the deadline-monotonic algorithm [10], which assigns tasks priorities in inverse proportion to their...

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...tems. Upper bounds on the load may be obtainable through empirical or analytical methods (for example, we may obtain upper bounds for load of real-time network traffic using the wellknown (σ,ρ) model =-=[13]-=-). Once an upper bound on load has been determined, we may apply the schedulability test of Theorem 1. Abdelzaher et al. [2] have previously considered the static-priority multiprocessor scheduling of...

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...ity scheduling algorithms include the rate-monotonic algorithm [11], in which higher priorities are assigned to tasks with smaller values of the period parameter, and the deadline-monotonic algorithm =-=[10]-=-, which assigns tasks priorities in inverse proportion to their relative deadline parameters: if dk < dℓ, then task τk has a higher priority than task τℓ (ties broken arbitrarily). Static-priority sch...

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...s of these schedulability tests. Keywords: Multiprocessor platforms; Static-Priority Scheduling; Schedulability analysis; Resource Augmentation. 1 Introduction Over the years, the sporadic task model =-=[12, 6]-=- has proven remarkably useful for the modelling of recurring processes that occur in hard-real-time systems. In this model, a sporadic task τk = (ek,dk,pk) is characterized by a worstcase execution re...

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...th each request a deadline and priority. From a different domain: real-time database systems (RTDBS) may characterize transactions by their arrival time, execution requirement, deadline, and priority =-=[1]-=-. In both these examples, the real-time instance characterization discussed in Section 2 can be used to model these systems. Upper bounds on the load may be obtainable through empirical or analytical ...

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...(ties broken arbitrarily). Static-priority scheduling algorithms are very commonly used in real-time systems; indeed, the RateMonotonic Analysis (RMA) real-time system design and analysis methodology =-=[9]-=- has become a standard in the domain of hard-real-time systems. One of the benefits of scheduling systems using static-priority scheduling is that higher-priority tasks are protected from errant behav...

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...l demand, normalized by interval length, of priority k or greater that can be generated by sporadic task system τ. It has been shown that load may be efficiently determined for sporadic task systems. =-=[5, 8, 15]-=- present algorithms that have pseudo-polynomial time complexity for task systems that have a system utilization ( �n i=1 ei/pi) strictly less than m. If a bounded amount of inaccuracy may be tolerated...

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...s of these schedulability tests. Keywords: Multiprocessor platforms; Static-Priority Scheduling; Schedulability analysis; Resource Augmentation. 1 Introduction Over the years, the sporadic task model =-=[12, 6]-=- has proven remarkably useful for the modelling of recurring processes that occur in hard-real-time systems. In this model, a sporadic task τk = (ek,dk,pk) is characterized by a worstcase execution re...

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... the research reported in this document is aimed at determining schedulability-analysis algorithms for sporadic task systems which are implemented upon multiprocessor platforms. Resource augmentation =-=[14]-=- provides a measure of the relative effectiveness and tightness of a given schedulability analysis algorithm. Resource augmentation works by comparing a given algorithm against the performance of a hy...

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...l demand, normalized by interval length, of priority k or greater that can be generated by sporadic task system τ. It has been shown that load may be efficiently determined for sporadic task systems. =-=[5, 8, 15]-=- present algorithms that have pseudo-polynomial time complexity for task systems that have a system utilization ( �n i=1 ei/pi) strictly less than m. If a bounded amount of inaccuracy may be tolerated...

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... instances. 4.2 The Scheduling of Sporadic Task Systems Recently, researchers have focussed on the multiprocessor static-priority scheduling of sporadic task systems. Baker [3, 4] and Bertogna et al. =-=[7]-=- have derived sufficient conditions for the multiprocessor, static-priority schedulability of sporadic task systems. The following theorem restates the schedulability test from Bertogna et al. [7]: Th...

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...nic scheduling of real-time instances. 4.2 The Scheduling of Sporadic Task Systems Recently, researchers have focussed on the multiprocessor static-priority scheduling of sporadic task systems. Baker =-=[3, 4]-=- and Bertogna et al. [7] have derived sufficient conditions for the multiprocessor, static-priority schedulability of sporadic task systems. The following theorem restates the schedulability test from...

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...l demand, normalized by interval length, of priority k or greater that can be generated by sporadic task system τ. It has been shown that load may be efficiently determined for sporadic task systems. =-=[5, 8, 15]-=- present algorithms that have pseudo-polynomial time complexity for task systems that have a system utilization ( �n i=1 ei/pi) strictly less than m. If a bounded amount of inaccuracy may be tolerated...

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...unds for load of real-time network traffic using the wellknown (σ,ρ) model [13]). Once an upper bound on load has been determined, we may apply the schedulability test of Theorem 1. Abdelzaher et al. =-=[2]-=- have previously considered the static-priority multiprocessor scheduling of real-time instances. Abdelzaher et al. propose a workload characterization called synthetic utilization. Let V (t) be the s...

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...nic scheduling of real-time instances. 4.2 The Scheduling of Sporadic Task Systems Recently, researchers have focussed on the multiprocessor static-priority scheduling of sporadic task systems. Baker =-=[3, 4]-=- and Bertogna et al. [7] have derived sufficient conditions for the multiprocessor, static-priority schedulability of sporadic task systems. The following theorem restates the schedulability test from...