This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Hughes, Z. M. Articles by Pont, M. J. Search for Related Content Social Bookmarking                         What's this?

Reducing the impact of task overruns in resource-constrained embedded systems in which a time-triggered software architecture is employed

Embedded Systems Laboratory, Department of Engineering, University of Leicester, University Road, Leicester LE1 7RH, UK

Michael J. Pont

Embedded Systems Laboratory, Department of Engineering, University of Leicester, University Road, Leicester LE1 7RH, UK, M.Pont{at}le.ac.uk

In embedded systems with severe resource constraints, a `time-triggered hybrid' (TTH) scheduler can be employed as an alternative to a fully pre-emptive design. A TTH approach allows the system designer to create a static schedule made up of 1) a collection of tasks that operate co-operatively and 2) a single — short — pre-emptive task. Although well matched to the needs of an important group of embedded systems (including control and data acquisition systems), the predictable performance of a TTH scheduler can be jeopardized if tasks exceed their predicted worst-case execution times. To address this problem, a novel TTH framework is described in this paper, which has `Task Guardians' associated with both the co-operative tasks and the pre-emptive task. The resulting framework is shown to have very limited resource requirements but highly predictable behaviour, even in the event of task overruns. Finally, a simplified design (supporting only co-operative tasks) is also described.

Key Words: control system • data-acquisition system • embedded system • hybrid scheduler • pre-emptive scheduler • scheduler implementation • Task Guardian • task overrun • time-triggered architecture • worst case execution time.

Transactions of the Institute of Measurement and Control, Vol. 30, No. 5, 427-450 (2008)
DOI: 10.1177/0142331207086183


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?