A Flexible Scheme for Scheduling Fault-Tolerant Real-Time Tasks on Multiprocessors

The recent introduction of multicore system-on-a-chip architectures for embedded systems opens a new range of possibilities for both increasing the processing power and improving the fault-robustness of real-time embedded applications. Fault-tolerance and performance are often contrasting requirements. Techniques to improve robustness to hardware faults are based on replication of hardware and/or software. Conversely, techniques to improve performance are based on exploiting inherent parallelism of multiprocessor architectures. In this paper, we propose a technique that allows the user to trade-off parallelism with fault-tolerance in a multicore hardware architecture. Our technique is based on a combination of hardware mechanisms and real-time operating system mechanisms. In particular, we apply hierarchical scheduling techniques to efficiently support fault-tolerant, fault-silent and non-fault-tolerant tasks in the same system.