A Fault–Tolerant Dynamic Scheduling Algorithm for Multiprocessor Real–Time Systems
نویسندگان
چکیده
Scheduling multiple versions of the tasks on different processors can provide fault tolerant. One of the models that is used for fault-tolerant scheduling of real–time tasks, namely, is the Primary backup (PB) model. In this approach, two versions are executed serially on two different processors and an acceptance test is used to check the result. The backup version is executed only if the output of the primary version fails the acceptance test, either due to the processor or the software fault. In this work, we address the scheduling of dynamically arriving real-time tasks with PB fault-tolerant requirements onto a set of processors in such a way that the versions of the tasks are feasible in the schedule. The objective of any dynamic real-time scheduling algorithm is to improve the guarantee ratio which is defined as the percentage of tasks, that arrived into the system, whose deadlines are met.
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