Abstract: The component density and the power and thermal properties of multicore and multithreaded processors demand energy and temperature awareness at all layers of the hardware/software interface. Energy-aware program optimization with hard performance constraints is an inherently dynamic optimization process, during which continuous power-performance profiling and rapid detection of energy-efficient operating points are essential.

In this talk I will discuss the foundations, design and implementation of an event-driven runtime scalability predictor (EDRSP) for simultaneous energy and performance optimization on multithreaded and multicore processors. EDRSP is an optimization tool which combines phase detection with online analysis of single-phase and cross-phase power-performance profiles collected from hardware event counters, to predict operating points of multithreaded code in which power consumption can be lowered without a performance penalty. I will present results from applications of EDRSP to energy-efficiency optimization on real multiprocessors with multithreaded and multicore processing components.

Short Bio: Dimitris Nikolopoulos is an Associate Professor of Computer Science at Virginia Tech since August 2006, after spending four years as an Assistant Professor of Computer Science at the College of William and Mary. Prior to assuming tenure-track faculty positions, he held the positions of Visiting Assistant Professor of the Department of Electrical and Computer Engineering and Visiting Research Assistant Professor of the Coordinated Science Laboratory, both at the University of Illinois, Urbana-Champaign.

Nikolopoulos conducts research in high-end and embedded parallel architectures, with emphasis on hardware/software support for runtime optimization in the execution engines and the memory system of processors with multiple execution contexts. He is a recipient of two early faculty career development awards from the National Science Foundation (NSF CAREER, 2004) and the United States Department of Energy (DOE ECPI, 2005), as well as five best paper awards including one from the Supercomputing (SC) Conference and one from the International Parallel and Distributed Processing Symposium (IPDPS). Nikolopoulos received his Doctorate degree in Computer Engineering from the University of Patras in Greece in 2000. He is a member of the IEEE Computer Society, ACM SIGARCH and the Technical Chamber of Greece.