Before revision:  The workload is greatly responsible for wasting the energy as well as limiting the size and the type of tasks the supercomputers can run . Case studies provide insight how the different contributions compete for dominating the resulting payload performance of the computing system, and how enhancing the technology made the computing+communication the dominating contribution in defining the efficiency of supercomputers.
After revision:  The workload is greatly responsible for wasting the energy as well as limiting the size and the type of tasks the supercomputers can run . Case studies provide insight how the different contributions compete for dominating the resulting payload performance of the computing system, and how enhancing the interconnection technology made computing+communication the dominating contribution in defining the efficiency of supercomputers.