High-performance computing (HPC) systems consume a significant amount of power, resulting in high operational costs, reduced reliability, and wasting of natural resources. Therefore, power consumption has become an increasingly important design constraint in high-performance clusters. In this regard, research on power-aware HPC has emerged. While most research has focused at understanding and utilizing applicationspsila behavior to scale down the CPU for energy savings, this paper demonstrates the positive impact of modern interconnects in delivering energy-efficiency in high-performance clusters. In this work, we first present the power-performance profiles of the Myrinet-2000 and Quadrics QsNet II  at the user-level and MPI-level in comparison to a traditional, non-offloaded Gigabit Ethernet. Such information enables us to devise a power-aware MPI runtime library that automatically and transparently performs message segmentation and re-assembly in order to increase energy savings. Secondly, by designing and evaluating a number of all-gather collectives, we argue that it is possible to increase the energy-efficiency of a cluster by optimizing its messaging layers.
['Reza Zamani', 'Ahmad Afsahi', 'Ying Qian', 'V. Carl Hamacher']
A feasibility analysis of power-awareness and energy minimization in modern interconnects for high-performance computing