The purpose of the Green500 is to provide a ranking of the most energy-efficient supercomputers in the world. For decades, the notion of "performance" has been synonymous with "speed" (as measured in FLOPS, short for floating-point operations per second). This particular focus has led to the emergence of supercomputers that consume egregious amounts of electrical power and produce so much heat that extravagant cooling facilities must be constructed to ensure proper operation. In addition, the emphasis on speed as the ultimate metric has caused other metrics such as reliability, availability, and usability to be largely ignored. As a result, there has been an extraordinary increase in the total cost of ownership (TCO) of a supercomputer.
In order to raise awareness to other performance metrics of interest (e.g., performance per watt and energy efficiency for improved reliability), the Green500 offers lists to encourage supercomputing stakeholders to ensure that supercomputers are only simulating climate change and not creating climate change.
History of The Green500
Historically, the Green500 started back in April 2005 – after a keynote talk by Dr. Wu-chun Feng at the IEEE IPDPS Workshop on High-Performance, Power-Aware Computing. The notion was then formally proposed a year later at the aforementioned workshop with a paper and associated talk entitled "Making a Case for a Green500 List," [ paper ] [ talk ]. A subsequent presentation at Clusters and Computational Grids for Scientific Computing 2006, "Global Climate Warming? Yes … In The Machine Room," led to more fervent interest, and ultimately, the announcement of the Green500 at SC|06. One year later at SC|07, the inaugural list was released and a new era of Green Supercomputing began.
Integration with TOP500
Starting with the list releases in June 2016, the Green500 project was integrated with TOP500, following nearly a decade of collaboration between the two projects. The TOP500 and Green500 lists will continue to remain separate, with a joint submission process and publication under the TOP500.org domain.