Fault-Tolerant Static Scheduling for Real-Time Distributed Embedded Systems
Résumé
This paper investigates fault-tolerance issues in real-time distributed embedded systems. Our goal is to propose solutions to automatically produce distributed and fault-tolerant code. We first characterize the systems considered by giving the main assumptions about the physical and logical architecture of these systems. In particular, we consider only processor failures, with a fail-stop behavior. Then, we give a state of the art of the techniques used for fault-tolerance. We also briefly present the «Algorithm Architecture Adequation» method (åa), used to obtain automaticall- y distributed code. The heart of AAA is a scheduling heuristic that produces automatically a static distributed schedule of a given algorithm onto a given distributed architecture. Our idea is to adapt the AAA method so that it produces automatically a static distributed and fault-tolerant schedule. For this purpose, we discuss several tracks of software implemented fault-tolerance within the AAA method. We present in details two new schedulin- g heuristics that achieve this goal.