Publication 2008 Issue No. 3 - March Abstract - Sharp Thresholds for Scheduling Recurring Tasks with Distance Constraints
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Sharp Thresholds for Scheduling Recurring Tasks with Distance Constraints
March 2008 (vol. 57 no. 3)
pp. 344-358
 ASCII Text x Sathish Gopalakrishnan, Marco Caccamo, Lui Sha, "Sharp Thresholds for Scheduling Recurring Tasks with Distance Constraints," IEEE Transactions on Computers, vol. 57, no. 3, pp. 344-358, March, 2008.
 BibTex x @article{ 10.1109/TC.2007.70808,author = {Sathish Gopalakrishnan and Marco Caccamo and Lui Sha},title = {Sharp Thresholds for Scheduling Recurring Tasks with Distance Constraints},journal ={IEEE Transactions on Computers},volume = {57},number = {3},issn = {0018-9340},year = {2008},pages = {344-358},doi = {http://doi.ieeecomputersociety.org/10.1109/TC.2007.70808},publisher = {IEEE Computer Society},address = {Los Alamitos, CA, USA},}
 RefWorks Procite/RefMan/Endnote x TY - JOURJO - IEEE Transactions on ComputersTI - Sharp Thresholds for Scheduling Recurring Tasks with Distance ConstraintsIS - 3SN - 0018-9340SP344EP358EPD - 344-358A1 - Sathish Gopalakrishnan, A1 - Marco Caccamo, A1 - Lui Sha, PY - 2008KW - Real-time systems and embedded systemsKW - Real timeKW - SchedulingKW - Constraint satisfactionKW - Heuristic methodsVL - 57JA - IEEE Transactions on ComputersER -
The problem of identifying suitable conditions for the schedulability of (non-preemptive) recurring tasks with deadlines is of great importance to real-time systems. In this article, motivated by the problem of scheduling radar dwells, we show that scheduling problems of this nature show a sharp threshold behavior with respect to system utilization. Sharp thresholds are associated with phase transitions: when the utilization of a task set is less than a critical value it can be scheduled almost surely, and when the utilization increases beyond the critical level almost no task set can be scheduled. We make connections to work on random graphs to prove sharp threshold behavior in the scheduling problem of interest. Using extensive experiments, we determine the threshold for the radar dwell scheduling problem and use it for performance optimization. The connections to random graph theory suggest new ways for understanding the average-case behavior of scheduling policies. These results emphasize the ease with which performance can be controlled in a variety of real-time systems.

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Index Terms:
Real-time systems and embedded systems, Real time, Scheduling, Constraint satisfaction, Heuristic methods
Citation:
Sathish Gopalakrishnan, Marco Caccamo, Lui Sha, "Sharp Thresholds for Scheduling Recurring Tasks with Distance Constraints," IEEE Transactions on Computers, vol. 57, no. 3, pp. 344-358, March 2008, doi:10.1109/TC.2007.70808