Multics Through The Looking Glass
Note 1 Setting smaller time slices gives each process a smaller time to attack other process's pages, and tends to produce a much more effective 'working set', raising both system efficiency and increasing system responsiveness.
Working Set is a term coined by Dr. Peter Denning to describe the
amount of memory actually required for the execution of a program within a
reasonable time period.
Multics does not exactly follow this definition since
the amount of memory that can be allocated to the desires of the process is
constrained by physical limits and the actions of other processes.
term would be Workable Set (the amount of memory permitted to be used),
but since Multics documentation uses 'working set' it will be used in this
This is a noticeable positive
feedback in the control system tending to degrade performance.
In the time since this paper was originally published theories have been somewhat improved. The greatest usefulness of the 'wc_max_eligible' is really in increasing the loop time required for the restricted work classes, so that they compete more equally with the other work classes that have more processes in them. This evens the paging demands of processes and brings out the workable set requirements more accurately.