Load-dependent energy saving in future home environments

Already hundreds of millions of PCs are found in homes, offering high computing capacity without being adequately utilized. This paper reveals the potential for energy saving in future home environments, which can be achieved by sharing resources, and concentrating 24/7 computation on a small number of PCs. We present three evaluation methods for assessing the expected performance. A newly created prototype is able to interconnect an arbitrary number of homes by using the free P2P-library FreePastry. The prototype is able to carry out task virtualization by sending virtual machines (VMs) from one home to another, most VMs being of size around 4 MB. We present measurement results from the prototype. We then describe a general model for download sharing, and compare performance results from an analytical model to results obtained from a discrete event simulator. The simulation results demonstrate that it is possible to reach almost optimal energy efficiency for this scenario.