Departmental Papers (CIS)

Date of this Version


Document Type

Journal Article


Schedulability analysis of hierarchical real-time embedded systems involves defining interfaces that represent the underlying system faithfully and then compositionally analyzing those interfaces. Whereas commonly used abstractions, such as periodic and sporadic tasks and their interfaces, are simple and well studied, results for more complex and expressive abstractions and interfaces based on task graphs and automata are limited. One contributory factor may be the hardness of compositional schedulability analysis with task graphs and automata. Recently, conditional task models, such as the recurring branching task model, have been introduced with the goal of reaching a middle ground in the tradeoff between expressivity and ease of analysis. Consequently, techniques for compositional analysis with conditional models have also been proposed, and each offer different advantages. In this work, we revisit those techniques, compare their advantages using an automotive case study, and identify limitations that would need to be addressed before adopting these techniques for use with real-world problems.

Subject Area

CPS Real-Time

Publication Source

ACM Transactions on Embedded Computing Systems (TECS)





Start Page

Article No. 2



Copyright/Permission Statement

© ACM 2013. This is the author's version of the work. It is posted here for your personal use. Not for redistribution. The definitive Version of Record was published in ACM Transactions on Embedded Computing Systems (TECS),


real-time and embedded systems, compositionality, state-based scheduling, real-time systems



Date Posted: 12 January 2015

This document has been peer reviewed.