We present detailed analytical models for estimating the energy dissipation in conventional caches as well as low energy cache architectures. The analytical models use the run time statistics such as hit/miss counts, fraction of read/write requests and assume stochastical distributions for signal values. These models are validated by comparing the power estimated using these models against the power estimated using a detailed simulator called CAPE (CAache Power Estimator). The analytical models for conventional caches are found to be accurate to within 2% error. However, these analyticalmodels over–predict the dissipations of low–power caches by as much as 30%. The inaccuracies can be attributed to correlated signal values and locality of reference, both of which are exploited in making some cache organizations energy efficient. Key words: Low–power caches, energy estimation, analytical models for energy dissipation.
Milind B. Kamble, Kanad Ghose