Properties of the Working-Set Model A program's working set W(t,T) at time t is the set of distinct pages among the T most recently referenced pages. Relations between the average working-set size, the missing-page rate, and the interreference-interval distribution may be derived both from time-average definitions and from ensemble-average (statistical) definitions. An efficient algorithm for estimating these quantities is given. The relation to LRU (least recently used) paging is characterized. The independent-reference model, in which page references are statistically independent, is used to assess the effects to interpage dependencies on working-set size observations. Under general assumptions, working-set size is shown to be normally distributed. CACM March, 1972 Denning, P. J. Schwartz, S. C. working-set model, paging, paging algorithms, program behavior, program modeling 4.3 CA720308 JB January 31, 1978 2:07 PM 1604 4 2373 1892 4 2373 1901 4 2373 1951 4 2373 2085 4 2373 2095 4 2373 2218 4 2373 2218 4 2373 2277 4 2373 2319 4 2373 2329 4 2373 2358 4 2373 2373 4 2373 2373 4 2373 2373 4 2373 2373 4 2373 2373 4 2373 2380 4 2373 2434 4 2373 2499 4 2373 2450 4 2373 2501 4 2373 2582 4 2373 2669 4 2373 2828 4 2373 2863 4 2373 2881 4 2373 2894 4 2373 2928 4 2373 2996 4 2373 3006 4 2373 3006 4 2373 3067 4 2373 3067 4 2373 1410 5 2373 1751 5 2373 1810 5 2373 1951 5 2373 2373 5 2373 2373 5 2373 2373 5 2373 2374 5 2373 2380 5 2373 2450 5 2373 2595 5 2373 2996 5 2373 3006 5 2373 3067 5 2373 1728 6 2373 1751 6 2373 1751 6 2373 1751 6 2373 1751 6 2373 1884 6 2373 1901 6 2373 2374 6 2373 2374 6 2373 2374 6 2373 2373 6 2373 2373 6 2373 2373 6 2373 2373 6 2373 2373 6 2373 2373 6 2373 2373 6 2373 2595 6 2373 2595 6 2373 2595 6 2373 2682 6 2373 2863 6 2373 2864 6 2373 3006 6 2373