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

In G. C. Buttazzo, Real-Time Syst., vol. 29, no. 1, pp. 5-26, 2005, the author empirically compared earliest deadline first (EDF) and rate monotonic (RM) scheduling algorithms and made a few EDF preemption behavior observations based on data obtained from the first 1000 time units of scheduling acti...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:IEEE embedded systems letters 2015-09, Vol.7 (3), p.89-91
Hauptverfasser: Brun, Adrien, Chunhui Guo, Shangping Ren
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext bestellen
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:In G. C. Buttazzo, Real-Time Syst., vol. 29, no. 1, pp. 5-26, 2005, the author empirically compared earliest deadline first (EDF) and rate monotonic (RM) scheduling algorithms and made a few EDF preemption behavior observations based on data obtained from the first 1000 time units of scheduling activities. However, based on test settings given in (G. C. Buttazzo, Real-Time Syst., vol. 29, no. 1, pp. 5-26, 2005), the first 1000 time units occupies only a small percentage of the entire task set's hyper-period. We extend EDF preemption behavior study by extending scheduling activities from the first small percentage of a hyper-period of a given task to the entire hyper-period. The extended experiments indicate that the number of preemptions occurred at the beginning of a task set's hyper-period does not necessarily represent the trend for the entire hyper-period. Hence, comparisons and conclusions made based on a small percentage of a scheduling interval over a task set's hyper-period may not be accurate. Second, the total number of preemptions within a task set's hyper-period does 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 also investigate the impact of execution time differences among tasks on the preemption behavior.
ISSN:1943-0663
1943-0671
DOI:10.1109/LES.2015.2452226