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In multiprocessor systems, redundant scheduling is a technique that trades processing power for increased reliability. One approach, called primary-backup task scheduling, is often used in real-time multiprocessor systems to ensure that deadlines are met in spite of faults. Briefly, it consists in scheduling a secondary task conditionally, in such a way that the secondary task actually gets executed only if the primary task (or the processor executing it) fails to terminate properly. Doing so avoids wasting CPU resources in the failure-free case, but primary and secondary tasks must then compete for resources in case of failure. To overcome this, overloading strategies, such as primary and backup overloading (PB) and backup-backup overloading (BB), aim at improving schedulability while retaining a certain level of reliability. In this paper, we propose a hybrid overloading technique based on extended PB overloading …