Optimization of Memory Hierarchies in Multiprogrammed Systems

The optimization of memory hierarchy involves the selection of types and sizes of memory devices such that the average access time to an information block is a minimum for a particular cost constraint. It is assumed that the frequency of usage of the information is known a priori. In this paper the optimization theory for a single task or program is reviewed and it is extended to a general case in multiprogramming when a number of tasks are executed concurrently. Another important extension treats the case when memories are available only in indivisible modules. Comparisons with conventional methods of solution as well as computational experience on the multiprogrammed and modular cases are given