PCube: Improving Power Efficiency in Data Center Networks

To alleviate the growing concern of energy waste in networked devices, we present PCube, a server-centric data center structure that conserves energy by varying bandwidth availability based on traffic demand. PCube not only supports a low-power mode for existing data centers offering full bisection bandwidth without hardware modification or re-wiring, but also provides an alternative for new data centers at a lower construction cost. The bandwidth demand could be dynamic and scalable in the optimal way when considering conserving the energy waste. To further reduce the cost, we take advantage of traffic locality, and propose Hybrid PCube, in order to offer different bandwidth to different servers. We use samples of traffic from a real-world production data center with full bisection bandwidth across thousands of servers, and evaluate our proposed algorithm using these collected samples. Our experimental results have shown convincing evidence that the proposed algorithm is able to substantially reduce energy costs incurred by networked devices in data centers.