Management of Cache Consistency
In any memory system of at least moderate complexity, maintaining cache consistency is a non-trivial matter. Cache consistency is loosely defined as follows:
In the presence of a cache, reads and writes behave (to a first order) no differently than if the cache were not there.
The choice of the word consistency in this book is deliberate, despite the confusion that may result within the architecture community (a memory-consistency model is a contract between programmer and memory system, and a cache-coherence scheme is an implementation of a given memory-consistency model; by cache consistency we mean something different). The reasons for the choice include the following:
• We would rather not invent ...