Green Computing in IEEE 802.3az-enabled Clusters

Although major eorts have been put into increasing the energy eciency of computing environments, energy-ecient networking has not been actively researched until 2006. The most prominent result of research in that area is the IEEE 802.3az standard, which allows active copper Ethernet links to save power by transitioning into low-power mode when no trac is expected on the link. In this research, we examine 802.3az and other energy-saving Ethernet technologies with the goal of applying them in high performance computing environments. Apart from studying these techniques from a theoretical point of view, we also examine their operation in a test environment, using dierent implementing devices. Using the results of our experiments, we also introduce an energy model, which aims to optimize the energy usage of applications in a high performance computing environment by taking energy-ecient Ethernet into account. Furthermore, we show a practical example of how to apply the proposed model to an actual application.