Indian Journal of Science and Technology

Abstract

Background/Objectives: Placing conflict cache lines in alternate set is proposed for set associative caches in literature. The conflicting lines are placed in one alternate set for each set. Methods/Statistical Analysis: This paper proposes architecture to place conflicting lines in set with maximum vacant ways in set associative caches. The model introduces one register per cache way with number of bits equal to number of cache sets. A sequential circuit using the register enables the cache ways of any set. The unoccupied ways are disabled. The proposed model is simulated with SPEC2K benchmarks. The power consumption is calculated using Quartus 2 tool and verilog code. Findings: An average improvement in power consumption of 68% for benchmarks with partial filled cache ways is observed with average memory access degradation of about 4.86%. A performance degradation in average memory access time of about 34% compared with direct mapped cache system and 3% compared with random placement algorithm is observed for the proposed system. The proposed model is for power consumption as is validated from the findings. The proposed model can be adapted for set associative caches to improve power consumption. Applications/Improvements: A model with optimal operational cache sets with methods to decrease power dissipation of sequential circuits, low power techniques for digital circuits can be used to improve the power consumption. 

Keywords: Average Memory Access Time, Conflict Miss, Power Saving, Set Associative Caches, Sequential Circuit