Association for Computing Machinery
The replacement policies for the Last-Level Caches (LLCs) are usually designed based on the access information available locally at the LLC. These policies are inherently sub-optimal due to lack of information about the activities in the inner-levels of the hierarchy. This paper introduces Cache Hierarchy-Aware Replacement (CHAR) algorithms for inclusive LLCs (or L3 caches) and applies the same algorithms to implement efficient bypass techniques for exclusive LLCs in a three-level hierarchy. In a hierarchy with an inclusive LLC, these algorithms mine the L2 cache eviction stream and decide if a block evicted from the L2 cache should be made a victim candidate in the LLC based on the access pattern of the evicted block.