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arXiv · 1404.0088

Toward Parametric Timed Interfaces for Real-Time Components

Youcheng Sun·Giuseppe Lipari·Étienne André·Laurent Fribourg
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Abstract

We propose here a framework to model real-time components consisting of concurrent real-time tasks running on a single processor, using parametric timed automata. Our framework is generic and modular, so as to be easily adapted to different schedulers and more complex task models. We first perform a parametric schedulability analysis of the components using the inverse method. We show that the method unfortunately does not provide satisfactory results when the task periods are consid- ered as parameters. After identifying and explaining the problem, we present a solution adapting the model by making use of the worst-case scenario in schedulability analysis. We show that the analysis with the inverse method always converges on the modified model when the system load is strictly less than 100%. Finally, we show how to use our parametric analysis for the generation of timed interfaces in compositional system design.

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Youcheng Sun, Giuseppe Lipari, Étienne André, Laurent Fribourg. 2014-04-01. Toward Parametric Timed Interfaces for Real-Time Components. https://doi.org/10.4204/eptcs.145.6

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