Multicore speedup models using frequency scaling with fixed power budget

Utilization of a core with delay faults by frequency scaling reduces performance degradation in a multicore processor. When the frequency of a delay fault core is decreased, frequencies of the rest cores can be increased within a fixed power budget since the amount of dynamic power is proportional to the clock frequency. We propose two speedup models based on modified Amdahl's law for the frequency scaling of a multicore architecture. From the models, we derive an attainable maximum speedup of a multicore processor with a delay fault core.