Apple Inc.
Scheduling threads based on mask assignments for activities

Abstract:

In an embodiment, an operating system for a computer system assigns each independently-schedulable code sequence to an activity. An activity may thus be associated with a group of related code sequences, such as threads that communicate with each other (whether or not they are part of the same program). When a code sequence is ready to be scheduled and it is not part of the current activity, it may preempt the current activity if the activity for the code sequence is not enabled and is not masked by the enabled activities. Each activity may define which other activities it masks. A flexible scheduling scheme may be devised based on the mask assignments for each activity.