On-premise storage servers account for a large share of data-center power, yet power-efficiency research has largely targeted compute and accelerators rather than storage. PACER is a power-saving subsystem for ARM-based all-flash storage servers that, unlike conventional CPU governors, is guided by storage-specific I/O metrics: it monitors the server’s operational state and predicts the performance impact of power-saving actions, staying within configurable tolerance bounds. On real-world traces it achieves 1.23× higher IOPS/watt than the native system, with power savings on MLPerf Storage workloads at no performance cost.

Published at IEEE MSST 2024.