Reducing TLB power requirements

Abstract

look-aside buffers (TLBs) are small caches to speed-up address translation in processors with virtual memory. This paper considers two issues: (1) a comparison of the power consumption of fully-associative, set-associative, and direct mapped TLBs for the same miss rate and (2) the proposal of modifications of the basic cells and of the structure of set-associative TLBs to reduce the power. The power evaluation is done using a model and the miss rates are obtained from simulations of the SPEC92 benchmark. With respect to (1) we conclude that for small TLBs (high miss rates) fully-associative TLBs consume less power but for larger TLBs (low miss rates) set-associative TLBs are better.