Issue No. 07 - July (2007 vol. 18)
Xiaorui Wang , IEEE
Chenyang Lu , IEEE
Xenofon Koutsoukos , IEEE
<p><b>Abstract</b>—Many real-time systems must control their CPU utilizations in order to meet end-to-end deadlines and prevent overload. Utilization control is particularly challenging in distributed real-time systems with highly unpredictable workloads and a large number of end-to-end tasks and processors. This paper presents the Decentralized End-to-end Utilization CONtrol (DEUCON) algorithm, which can dynamically enforce the desired utilizations on multiple processors in such systems. In contrast to centralized control schemes adopted in earlier works, DEUCON features a novel decentralized control structure that requires only localized coordination among neighbor processors. DEUCON is systematically designed based on recent advances in distributed model predictive control theory. Both control-theoretic analysis and simulations show that DEUCON can provide robust utilization guarantees and maintain global system stability despite severe variations in task execution times. Furthermore, DEUCON can effectively distribute the computation and communication cost to different processors and tolerate considerable communication delay between local controllers. Our results indicate that DEUCON can provide a scalable and robust utilization control for large-scale distributed real-time systems executing in unpredictable environments.</p>
Real-time and embedded systems, feedback control real-time scheduling, distributed systems, end-to-end task, decentralized model predictive control.
C. Lu, X. Wang, X. Koutsoukos and D. Jia, "DEUCON: Decentralized End-to-End Utilization Control for Distributed Real-Time Systems," in IEEE Transactions on Parallel & Distributed Systems, vol. 18, no. , pp. 996-1009, 2007.