Phase-based tuning methodologies specialize system parameters for each application phase of execution. Parameters are varied during execution, as opposed to remaining fixed as in an application-based tuning methodology. Prior work and logic suggests phase-based tuning may provide significant savings over application-based tuning. We investigate this hypothesis using a detailed cache model and tune a highly-configurable cache on a per-phase basis compared to tuning once per application, and found phase-based tuning to yield improvements of up to 37% in performance and 20% in energy over application-based tuning. Furthermore, we extend previous phase-based tuning of a configurable cache by significantly increasing configurability and show 14% energy improvement compared to previous methods. In addition, we quantify the overhead imposed due to cache reconfiguration. Categories and Subject Descriptors B.3.2 [Design Styles]: Cache Memories General Terms Design. Keywords Caches, configurabl...