A Hierarchical Scheduling Model for Dynamic Soft-Realtime System

Authors Vladimir Nikolov, Stefan Wesner, Eugen Frasch, Franz J. Hauck

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Vladimir Nikolov
Stefan Wesner
Eugen Frasch
Franz J. Hauck

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Vladimir Nikolov, Stefan Wesner, Eugen Frasch, and Franz J. Hauck. A Hierarchical Scheduling Model for Dynamic Soft-Realtime System. In 29th Euromicro Conference on Real-Time Systems (ECRTS 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 76, pp. 7:1-7:23, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)


We present a new hierarchical approximation and scheduling approach for applications and tasks with multiple modes on a single processor. Our model allows for a temporal and spatial distribution of the feasibility problem for a variable set of tasks with non-deterministic and fluctuating costs at runtime. In case of overloads an optimal degradation strategy selects one of several application modes or even temporarily deactivates applications. Hence, transient and permanent bottlenecks can be overcome with an optimal system quality, which is dynamically decided. This paper gives the first comprehensive and complete overview of all aspects of our research, including a novel CBS concept to confine entire applications, an evaluation of our system by using a video-on-demand application, an outline for adding further resource dimension, and aspects of our protoype implementation based on RTSJ.
  • Real-Time
  • Scheduling
  • Hierarchical
  • Dynamic


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