Title: | Spare CASH: Reclaiming Holes to Minimize Aperiodic Response Times in a Firm Real-Time Environment |
Author(s): | Thomas, Deepu C.; Gopalakrishnan, Sathish; Caccamo, Marco; Lee, Chang-Gun |
Subject(s): | Real-time systems |
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. |
Issue Date: | 2005-04 |
Genre: | Technical Report |
Type: | Text |
URI: | http://hdl.handle.net/2142/11019 |
Other Identifier(s): | UIUCDCS-R-2005-2566 |
Rights Information: | You are granted permission for the non-commercial reproduction, distribution, display, and performance of this technical report in any format, BUT this permission is only for a period of 45 (forty-five) days from the most recent time that you verified that this technical report is still available from the University of Illinois at Urbana-Champaign Computer Science Department under terms that include this permission. All other rights are reserved by the author(s). |
Date Available in IDEALS: | 2009-04-17 |