Performance Analysis of Variable Number of Sets in Fully Associative Cache

Energy consumption in caches depends on the number of sets/ways that are active during program execution. A fully associative cache with modified address translation using XOR function has been proposed in literature. This paper compares the performance of this model with direct, set associative, fully associative memory of same size and analyzes the energy consumed in the proposed model. Expressions for the average memory access time for the proposed model are stated. Energy consumed in the proposed model is compared with the direct, set associative and fully associative cache of same size and conditions for outperforming them are derived. Simulations are done on SPEC 2000 benchmarks. The performance with respect to average memory access time is found to be equal to direct, set associative, fully associative memory of same size for the chosen parameters. The energy consumed is comparable with a set associative cache of same size and ways. An improvement in the energy consumed of 99% is seen in the case of the fully associative memory of same size.