Directions for memory hierarchies and their components: Research and development

The memory hierarchy is usually the largest identifiable part of a computer system and making effective use of it is critical to the operation and use of the system. We consider the levels of such a memory hierarchy and describe the state of the art and likely directions for both research and development. Algorithmic and logical features of the hierarchy not directly associated with specific components are also discussed. Among the problems we believe to be the most significant are the following: (a) evaluate the effectiveness of gap filler technology as a level of storage between main memory and disk, and if it proves to be effective, determine how/where it should be used, (b) develop algorithms for the use of mass storage in a large comguter system and (c) determine how cache memories should be implemented in very large, fast multiprocessor systems.