Montgolfier: Latency-Aware Power Management System for Heterogeneous Servers

Heterogeneous servers have long been introduced to improve energy efficiency in warehouse-scale computers(WSCs). However, running latency-critical web-services on heterogeneous servers is still challenging because the overheads of transition between such servers heavily impact overall benefits and performance. We propose Montgolfier, a runtime power management system based on a latency-aware feedback control mechanism. It consolidates wimpy and brawny servers into composite nodes to improve energy efficiency while ensuring QoS for latency-critical applications. Montgolfier effectively mitigates the effect of transition overhead between servers with dynamically load prediction and accurately provides thin-provisioned configurations in fine-grain manner for fluctuating loads. Our evaluation results show that Montgolfier reduces energy consumption by up to 34.9% without violating any QoS constraints.