Essentials of Computer Organization and Architecture, 5th Edition

6.3   THE MEMORY HIERARCHY

One of the most important considerations in understanding the performance capabilities of a modern processor is the memory hierarchy. Unfortunately, as we have seen, not all memory is created equal, and some types are far less efficient and thus cheaper than others. To deal with this disparity, today’s computer systems use a combination of memory types to provide the best performance at the best cost. This approach is called hierarchical memory. As a rule, the faster memory is, the more expensive it is per bit of storage. By using a hierarchy of memories, each with different access speeds and storage capacities, a computer system can exhibit performance above what would be possible without a combination of the various ...