Toward Parametric Timed Interfaces for Real-Time Components

TL;DR

This paper introduces a modular framework using parametric timed automata for modeling and analyzing real-time components, focusing on schedulability and timed interface generation in systems with concurrent tasks.

Contribution

It presents a generic, adaptable model for real-time components, addresses limitations of the inverse method in parametric analysis, and proposes a solution for reliable schedulability analysis.

Findings

Inverse method converges on the modified model under system load less than 100%

The framework effectively generates timed interfaces for compositional system design

Identifies and addresses issues with parameterized task periods in schedulability analysis

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.