From ACM TechNews,
The most recent version of the Green500 list was revealed at the SC08 supercomputing conference in Austin, Texas, marking the first time that high-performance computers have been capable of executing more than 500 million floating-point operations/second for every watt of energy used. The most energy-efficient supercomputer, a 2,016-processor machine at the University of Warsaw’s Interdisciplinary Center for Mathematical and Computational Modeling, produced more than 536 megaflops per watt. The University of Warsaw supercomputer and the next top-six systems on the list all run IBM’s multicore Cell Broadband Engine (Cell/B.E.) processor, and four of those systems use IBM’s new QS22 blade server. Overall, the participating supercomputers showed a 17 percent improvement in energy efficiency over the previous Green500 list, which was created in 2006 by Virginia Tech associate professors Wu Feng and Kirk Cameron as a way of encouraging supercomputer developers to pay greater attention to how much energy their products consume. The Green500 rankings are determined by dividing the Linpack score, taken as part of the Top500 rankings, by the average amount of wattage used during the test. The machine that was first on the Top500 list, the Los Alamos National Laboratory’s IBM-based Roadrunner, ranked ninth on the Green500 list. The widespread use of systems running specialized processors could lead to more energy-efficient machines. Specialized processors such as the Cell/B.E., Nvidia’s Cuda-based graphical processors, or plug-in field-programmable gate arrays can provide more flops per watt than general-use processors.
