Fault-Tolerant Real-Time Mach: A Timeline-based approach

Even though real-time systems have the stringent constraint of completing tasks before their deadlines, many existing real-time operating systems do not implement fault tolerance capabilities. In this paper we describe the development and implementation of a non-preemptive fault tolerant real-time policy for aperiodic dynamic tasks. We implemented non-preemptive fault-tolerant scheduling and recovery mechanism in the RT Mach operating system. The scheme is based on providing sufficient slack for each task to re-execute in case of transient and intermittent faults. In this implementation on RT Mach we created new kernel mechanisms and took advantage of some existing ones, with relatively few modifications. Resource Reclaiming: Pitt-TR 97-01, submitted to RTAS '97 January 1997 1 Introduction In many applications correct execution of tasks is determined not only by logical correctness but also by satisfying certain temporal constraints. Examples of real-time applications can be found ..