Working set

Working set is a concept in computer science which defines the amount of memory that a process requires in a given time interval.

Peter Denning (1968) defines “the working set of information ${\displaystyle W(t,\tau )}$ of a process at time ${\displaystyle t}$ to be the collection of information referenced by the process during the process time interval ${\displaystyle (t-\tau ,t)}$”. Typically the units of information in question are considered to be memory pages. This is suggested to be an approximation of the set of pages that the process will access in the future (say during the next ${\displaystyle \tau }$ time units), and more specifically is suggested to be an indication of what pages ought to be kept in main memory to allow most progress to be made in the execution of that process.

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