Generalized Working Sets for Segment Reference Strings The working-set concept is extended for programs that reference segments of different sizes. The generalized working-set policy (GWS) keeps as its resident set those segments whose retention costs do not exceed their retrieval costs. The GWS is a model for the entire class of demand-fetching memory policies that satisfy a resident-set inclusion property. A generalized optimal policy (GOPT) is also defined; at its operating points it minimizes aggregated retention and swapping costs. Special cases of the cost structure allow GWS and GOPT to simulate any known stack algorithm, the working set, and VMIN. Efficient procedures for computing demand curves showing swapping load as a function of memory usage are developed for GWS and GOPT policies. Empirical data from an actual system are included. CACM September, 1978 Denning, P. Slutz, D. Database referencing, memory management, optimal memory policies, paging, program behavior, program measurement, segmentation, working sets 4.30 8.10 CA780905 DH February 5, 1979 11:20 AM 1892 4 3067 1901 4 3067 2085 4 3067 2095 4 3067 2218 4 3067 2277 4 3067 2319 4 3067 2329 4 3067 2358 4 3067 2373 4 3067 2373 4 3067 2374 4 3067 2380 4 3067 2380 4 3067 2434 4 3067 2499 4 3067 2450 4 3067 2450 4 3067 2501 4 3067 2582 4 3067 2595 4 3067 2669 4 3067 2828 4 3067 2863 4 3067 2863 4 3067 2881 4 3067 2928 4 3067 2996 4 3067 2996 4 3067 2996 4 3067 3000 4 3067 3006 4 3067 3006 4 3067 3006 4 3067 3006 4 3067 3067 4 3067 3067 4 3067 3067 4 3067 3067 4 3067 3067 4 3067 3067 4 3067 3067 4 3067 3067 4 3067 1751 5 3067 2373 5 3067 2374 5 3067 2595 5 3067 2682 5 3067 2863 5 3067 2864 5 3067 3006 5 3067 3067 5 3067 3067 5 3067 3067 5 3067