Advanced Micro Devices, Inc.
Hybrid lower-level cache inclusion policy for cache hierarchy having at least three caching levels

Abstract:

A system includes one or more processor cores and a cache hierarchy. The cache hierarchy includes a first-level cache, a second-level cache, and a third-level cache. The cache hierarchy further includes cache hierarchy control logic configured to implement a caching policy in which each cacheline cached in the first-level cache has a copy of the cacheline cached in at least one of the second-level cache and the third-level cache. The caching policy further provides that an eviction of a cacheline from the second-level cache does not trigger an eviction of a copy of that cacheline from the first-level cache, and that an eviction of a cacheline from the third-level cache triggers the cache hierarchy control logic to evict a copy of that cacheline from the first-level cache when the cacheline is not present in the second-level cache.