Beyond Power Proportionality: Designing Power-Lean Cloud Storage

We present a power-lean storage system, where racks of servers, or even entire data center shipping containers, can be powered down to save energy. We show that racks and containers are more than the sum of their servers, and demonstrate the feasibility of designing a storage system that powers them up and down on demand further, we show that such a system would save an order of magnitude more energy than current disk-based power-proportional storage systems. Our simulation results using file system traces from the Internet Archive show over 44% energy savings, a 5x improvement over disk-based power management systems, without performance impact. We explore the tradeoffs in choosing the right unit to power off/on, and present an automated framework to compute the optimal power management unit for different scenarios.