Leakage energy reduction for hard real-time caches

Cache leakage reduction techniques usually compromise time predictability, which are not desirable for real-time systems. In this work, we extend the cache decay and drowsy cache techniques within the hardware-based Performance Enhancement Guaranteed Cache (PEG-C) architecture. The PEG-C can dynamically monitor the performance penalties caused by using leakage energy reduction techniques to ensure that the worst-case execution time (WCET) is better than the case without using any cache. At the same time, the leakage energy of caches can be reduced significantly.