working set


working set

[′wərk·iŋ ′set] (computer science) The smallest collection of instruction and data words of a given computer program which should be loaded into the main storage of a computer system so that efficient processing is possible.

working set

(architecture)The set of all pages (in a paging virtual memory system) used by a process during some time interval.

As a result of locality of reference, the working setfrequently consists of a relatively small fraction of aprocess's total virtual memory pages. While a process'sentire working set is in physical memory the process willrun without page faults. If the working set is too largefor available physical memory, the process causes frequentpage faults.

In a multitasking environment, information about which pagesare in each process's working set allows the memory managementsystem to improve CPU efficiency by prepaging (also calledthe working set model).

["Modern Operating Systems", Andrew S. Tanenbaum, pub.Prentice Hall, Inc. 1992].