Average Rate Speed Scaling

Speed scaling is a power management technique that involves dynamically changing the speed of a processor. This gives rise to dual-objective scheduling problems, where the operating system both wants to conserve energy and optimize some Quality of Service (QoS) measure of the resulting schedule. Yao, Demers, and Shenker [8] considered the problem where the QoS constraint is deadline feasibility and the objective is to minimize the energy used. They proposed an online speed scaling algorithm Average Rate (AVR) that runs each job at a constant speed between its release and its deadline. They showed that the competitive ratio of AVR is at most (2α)α /2 if processor running at speed s uses power sα . We show the competitive ratio of AVR is at least ((2 − δ)α)α /2, where δ is some function of α that approaches zero as α approaches infinity. This shows that the competitive analysis of AVR by Yao, Demers, and Shenker is essentially tight, at least for large α. We also give an al...

• Type: Journal
• Year: 2011
• Where: ALGORITHMICA
• Authors: Nikhil Bansal, David P. Bunde, Ho-Leung Chan, Kirk Pruhs
• Keywords: ALGORITHMICA 2011, Algorithms, Approaches Zero, Management Technique, Shenker