PROJECT TITLE :

A Note on the EDF Preemption Behavior in “Rate Monotonic Versus EDF: Judgment Day”

ABSTRACT:

In G. C. Buttazzo, Real-Time Syst., vol. 29, no. one, pp. five-26, 2005, the author empirically compared earliest deadline initial (EDF) and rate monotonic (RM) scheduling algorithms and made some EDF preemption behavior observations based on data obtained from the primary a thousand time units of scheduling activities. However, primarily based on check settings given in (G. C. Buttazzo, Real-Time Syst., vol. 29, no. 1, pp. 5-26, 2005), the first one thousand time units occupies solely a tiny share of the complete task set's hyper-amount. We have a tendency to extend EDF preemption behavior study by extending scheduling activities from the first small share of a hyper-period of a given task to the entire hyper-amount. The extended experiments indicate that the number of preemptions occurred at the start of a task set's hyper-amount will not essentially represent the trend for the entire hyper-period. Hence, comparisons and conclusions made primarily based on a little share of a scheduling interval over a task set's hyper-period may not be accurate. Second, the full range of preemptions within a task set's hyper-amount will not decrease when the task set total utilization increases which is different from the observation obtained in (G. C. Buttazzo, Real-Time Syst., vol. 29, no. 1, pp. 5-26, 2005). We tend to also investigate the impact of execution time differences among tasks on the preemption behavior.