Title: SEESAW: Using Superpages to Improve VIPT Caches

Abstract:
Hardware caches balance fast lookup, high hit rates, energy efficiency, and simplicity of implementation. For L1 caches
however, achieving this balance is difficult because of constraints imposed by virtual memory. L1 caches are usually
virtually-indexed and physically tagged (VIPT), but this means that they must be highly associative to achieve good capacity.
Unfortunately, excessive associativity compromises performance by degrading access times without significantly boosting
hit rates, and increases access energy.
We propose SEESAW to overcome this problem. SEESAW leverages the increasing ubiquity of superpages – since super- pages
have more page offset bits, they can accommodate VIPT caches with more sets than what is traditionally possible with only
base page sizes. SEESAW dynamically reduces the number of ways that are looked up based on the page size, improving
performance and energy. SEESAW requires modest hardware and no OS or application changes.