Title | Spare CASH: reclaiming holes to minimize aperiodic response times in a firm real-time environment |
Publication Type | Conference Paper |
Year of Publication | 2005 |
Authors | Thomas, D. C., S. Gopalakrishnan, M. Caccamo, and C. - G. Lee |
Conference Name | Real-Time Systems, 2005. (ECRTS 2005). Proceedings. 17th Euromicro Conference on |
Pagination | 147 - 156 |
Date Published | jul. |
Keywords | aperiodic request servicing, aperiodic response time minimization, firm real-time environment, periodic task scheduling, real-time systems, scheduling, spare capacity, spare CASH |
Abstract | Scheduling periodic tasks that allow some instances to be skipped produces spare capacity in the schedule. Only a fraction of this spare capacity is uniformly distributed and can easily be reclaimed for servicing aperiodic requests. The remaining fraction of the spare capacity is non-uniformly distributed, and no existing technique has been able to reclaim it. We present a method for improving the response times of aperiodic tasks by identifying the non-uniform holes in the schedule and adding these holes as extra capacity to the capacity queue of the CASH mechanism. The non-uniform holes can account for a significant portion of spare capacity, and reclaiming this capacity results in considerable improvements to aperiodic response times. |
URL | http://dx.doi.org/10.1109/ECRTS.2005.28 |
DOI | 10.1109/ECRTS.2005.28 |