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Draco: Efficient Resource Management for Resource-Constrained Control Tasks
January 2009 (vol. 58 no. 1)
pp. 90-105
Pau Martí, Technical University of Catalonia, Vilanova i la Geltrú
Caixue Lin, University of California, Santa Cruz, Santa Cruz
Scott A. Brandt, University of California, Santa Cruz, Santa Cruz
Manel Velasco, Technical University of Catalonia, Barcelona
Josep M. Fuertes, Technical University of Catalonia, Barcelona
In many application areas, including control systems, careful management of system resources is key to providing the best application performance. Traditional control systems with multiple control loops statically allocate a fixed portion of the system resources to each controller based on their average or worst-case resource requirements. However, controllers' resource needs vary depending on the jobs they perform and the state of the systems they control. A controller of a plant operating close to its equilibrium requires fewer resources than a controller of a plant operating far from its equilibrium point. The Draco dynamic rate control system exploits this fact by dynamically allocating resources to control systems based on system state. Our research demonstrates that Draco provides significantly better overall control performance with much less resources than static controllers. Our experimental evaluation shows that in the control scenarios we examined Draco provides up to 25% better control performance with 30% less resources.

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Index Terms:
Real-time systems and embedded systems, Scheduling, Command and control
Pau Martí, Caixue Lin, Scott A. Brandt, Manel Velasco, Josep M. Fuertes, "Draco: Efficient Resource Management for Resource-Constrained Control Tasks," IEEE Transactions on Computers, vol. 58, no. 1, pp. 90-105, Jan. 2009, doi:10.1109/TC.2008.136
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