2928	 Hardware Estimation of a Process Primary Memory Requirements	 A minor hardware extension to the Honeywell processor is demonstrated to allow the primary memory requirements of a process in Multics to be approximated. The additional hardware required for this estimate to be computed consists of a program accessible register containing the miss rate of the associative memory used for page table words. This primary memory requirement estimate was employed in an experimental version of Multics to control the level of multiprogramming in the system and to bill for memory usage. The resulting system s tuning parameters display configuration insensitivity and it is conjectured that the system would also track shifts in the referencing characteristics of its workload and keep the system in tune. primary memory requirement virtual memory level of multiprogramming associative memory working set resource allocation LRU stack model referencing characteristics
