Departmental Papers (CIS)

Date of this Version

December 2004

Document Type

Conference Paper


Copyright 2004 IEEE. Reprinted from Proceedings of the 25th IEEE International Real-Time Systems Symposium 2004, pages 57-67.
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Our goal is to develop a compositional real-time scheduling framework so that global (system-level) timing properties can be established by composing independently (specified and) analyzed local (component-level) timing properties. The two essential problems in developing such a framework are (1) to abstract the collective real-time requirements of a component as a single real-time requirement and (2) to compose the component demand abstraction results into the system-level real-time requirement. In our earlier work, we addressed the problems using the Liu and Layland periodic model. In this paper, we address the problems using another well-known model, a bounded-delay resource partition model, as a solution model to the problems. To extend our framework to this model, we develop an exact feasibility condition for a set of bounded-delay tasks over a bounded-delay resource partition. In addition, we present simulation results to evaluate the overheads that the component demand abstraction results incur in terms of utilization increase. We also present new utilization bound results on a bounded-delay resource model.


real-time systems, real-time composition, real-time scheduling, multi-level scheduling, component-based design



Date Posted: 15 March 2005

This document has been peer reviewed.