Overhead effects in real-time preemptive schedules
David L. Rhodes, Wayne H. Wolf · 1999
The hard real-time schedulability of dependent taskgraphs is studied for single bus homogeneous multiprocessor systems.A model which includes interrupts and context switching as well as bus contention is developed.The model captures real-time operating system effects aimed at realistically modeling both intra-processor and inter-processor communications.A robust scheduler is used to assess the impact of interrupt service time (ET) and context switching time (CST) on schedulability.For the class of task-graphs studied, it is shown that schedulability is a nonlinear function of only the weighted sum of IST and CST.