CAM Colloquium: Douglas Down (McMaster University) - Energy-Aware Scheduling on Heterogeneous Servers


Frank H. T. Rhodes Hall 655


Abstract: This talk is concerned with the scheduling of a multiserver system where servers are heterogeneous in terms of both their speeds and their usage (energy) costs. The goal is to determine scheduling policies that minimize a combination of holding costs (cost for waiting) of tasks and energy/usage costs of servers. The motivation is designing task scheduling policies for reducing energy consumption in data centers. We discuss some previous results on determining optimal scheduling policies for clearing systems (there are no arrivals) and systems with arrivals as well as whether tasks can be reassigned or not. A key step in determining optimality of a scheduling policy is proving relations between an individually optimal (greedy) scheduling policy and a socially optimal scheduling policy. This relation will be discussed in some detail. Finally, two recent extensions will be presented - incorporating a thermal model for servers and service rate control.

Bio: Douglas Down is a Professor in the Department of Computing and Software and the Acting Academic Director of the Computing Infrastructure Research Centre, both at McMaster University in Hamilton, Ontario, Canada. He received his PhD in Electrical Engineering from the University of Illinois at Urbana-Champaign. His research interests lie in the area of queueing theory, performance modelling of computer systems and control systems design for data centers.