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 ...

A scheduling algorithm is the one which decides a schedule for a given set of tasks. There are a number of algorithms for task scheduling on a processor. Some of these algorithms are used for scheduling tasks on a multiprocessor system either under the partitioning scheme or under the global scheme. The optimal algorithm is the Earliest Deadline First (EDF) algorithm. If a set of task cannot be...

Packet networks are currently enabling the integration of traffic with a wide range of characteristics that extend from video traffic with stringent QoS requirements to the best-effort traffic requiring no guarantees. QoS guarantees can be provided in conventional packet networks by the use of proper packet scheduling algorithms. As a computer revolution, many scheduling algorithms have been pr...

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Real time systems are systems in which there is a commitment for timely response by the computer to external stimuli. Real time applications have to function correctly even in presence of faults. Fault tolerance can be achieved by either hardware or software or time redundancy. Safety-critical applications have strict time and cost constraints, which means that not only faults have to be tolera...

Inhaltsverzeichnis Abbildungsverzeichnis v Tabellenverzeichnis ix Verzeichnis der verwendeten Symbole xi 1 Einleitung 1 1.

We present a scheduling architecture that enables the implementation of deadline-based scheduling policies. The architecture is used to give real-time capabilities to a custom Java virtual machine. This framework retains a clear separation between generic kernel mechanisms and upper level scheduling classes. A pure earliest deadline first algorithm can be implemented, but enhanced policies such...

We propose in this paper, a method to automatically map runnables (blocks of code with dedicated functionality) with real-time constraints to tasks (or threads). We aim at reducing the number of tasks runnables are mapped to, while preserving the schedulability of the initial system. We consider independent tasks running on a single processor. Our approach has been applied with fixed-task or fi...

The Controller Area Network has a maximum transmission rate of 1 Mbitk and its fixed priorities-based medium access control limits the maximum bus utilisation when timeliness guarantees are required. An implementation of earliest deadline first (EDF) message scheduling on CAN, based on the F’IT CAN protocol, is presented, which allows higher utilisation factors with timeliness guarantees. The a...