CPU Cache - Cache Hierarchy in A Modern Processor

Cache Hierarchy in A Modern Processor

Modern processors have multiple interacting caches on chip.

The operation of a particular cache can be completely specified by:

• the cache size
• the cache block size
• the number of blocks in a set
• the cache set replacement policy
• the cache write policy (write-through or write-back)

While all of the cache blocks in a particular cache are the same size and have the same associativity, typically "lower-level" caches (such as the L1 cache) have a smaller size, have smaller blocks, and have fewer blocks in a set, while "higher-level" caches (such as the L3 cache) have larger size, larger blocks, and more blocks in a set.