We present a general purpose model and schedulability condition for supporting multiple service classes using bandwidth resource partitioning. The model supports guaranteed communication performance for real-time multimedia tra c via an Earliest Deadline First (EDF) packet transmission policy. We show how the EDF model can incorporate the e ect of multiple service classes sharing the same trans...

In this paper we implement the EDF-VD (Earliest Deadline First with Virtual Deadline) algorithm described in [1] for scheduling mixed-criticality, realtime task systems on preemptive uniprocessor platforms. We compare the scheduling overheads of this algorithm with the scheduling overheads of the well known EDF (Earliest Deadline First) algorithm for scheduling realtime task systems on preempti...

Earliest Deadline First scheduling with per-node traffic shaping (RC-EDF) has the largest schedulable region among all practical policies known today and has been considered a good solution for providing end-to-end packet delay bounds. In order to harness the traffic burstiness inside a network to satisfy the schedulability condition of EDF, pernode traffic shaping has been believed to be neces...

Earlier studies have observed that in moderately-loaded real-time systems, using an earliest deadline policy to schedule tasks results in the fewest missed deadlines. However, when the real-time system is overloaded an earliest deadline schedule performs worse than most other policies. This is due to the earliest deadline giving the highest priority to the tasks that are close to missing their ...

The contention-free policy has received attention in real-time multiprocessor scheduling owing to its wide applicability and significant improvement in offline schedulability guarantees. Utilizing the notion of contention-free slots in which the number of active jobs is smaller than or equal to the number of processors, the policy improves the schedulability by offloading executions in contendi...

This paper designs and analyzes the performance of a communication scheduler that cooperates with each other over the dual-channel wireless network, aiming at enhancing reliability and timeliness of time-sensitive applications on embedded devices. The proposed scheme consists of (1) evenly partitioning the stream set into two identical ones, (2) applying EDF (Earliest Deadline First) policy on ...

We present a method for calculating the minimum EDF-feasible deadline. The algorithm targets periodic tasks with hard real-time guarantees, that are to be feasibly scheduled with EDF (Earliest Deadline First). The output is the smallest possible deadline required for feasibility, of the task most recently requested. The good thing with our algorithm is that it has the same timecomplexity as the...

This paper presents a sensitivity analysis for the dimensioning of realtime systems in which sporadic tasks are executed according to the preemptive Earliest Deadline First (EDF) scheduling policy. The timeliness constraints of the tasks are expressed in terms of late termination deadlines. New results for EDF are shown, which enable us to determine the C-space feasibility domain valid for any ...

This paper analyzes fluid scale asymptotics of two models generalized Jackson networks employing the earliest deadline first (EDF) policy. One applies ‘soft’ EDF policy, where deadlines are used to determine priority but jobs do not renege, and other implements ‘hard’ EDF, renege when expire, postponed with each migration a new station. The arrival rates, distribution service capacity allowed f...

The Quality of Service (QoS) of real time applications is affected in a rather direct manner by the timely delivery of Application-level Data Units (ADUs) which are typically mapped into several Network-level Data Units (NDUs). As a consequence, it would be reasonable to associate a common deadline with all the NDUs in one ADU and develop a scheduling policy that aims to maximise the number of ...