Fault-Tolerant Scheduling of Real-Time Tasks on Heterogeneous Systems

Fault-tolerance is very important in hard real-time heterogeneous systems, especially in safety-critical systems, since faults can result in a disaster. Such systems require that an application can operate normally even when a processor is subject to failures under a given time constraint. In this paper, we tackle the problem of scheduling tasks on heterogeneous systems with the constraint of time and the ability of fault-tolerance, while considering communication overhead. The problem is NP-hard and we propose a heuristic algorithm DB-FTSA to solve it. The heuristic algorithm is based on an active replication scheme, capable of supporting several transient failures. It incorporates the reliability calculation into the active replication scheme, and can dynamically find out fault-tolerant tasks. Experimental results demonstrate that our proposed algorithm can effectively improve the system reliability under the given time constraint.