Work-in-Progress: Strong APA Scheduling in a Real-Time Operating System

Arbitrary processor affinities are used in multiprocessor systems to specify the processors on which a task can be scheduled. However, affinity constraints can prevent some high priority real-time tasks from being scheduled, while lower priority tasks execute. This paper presents an implementation and evaluation of the Strong Arbitrary Processor Affinity scheduling on a real-time operating system, an approach that not only respects user-defined affinities, but also supports migration of a higher priority task to allow execution of a task limited by affinity constraints. Results show an improvement in response and turnaround times of higher priority tasks.