Energy Efficiency and Power Measurements: an Industrial Survey

Abstract

Context. In the last few years, the energy consumption of data centers increased substantially. Currently, energy costs are the main expenditure in data center ownership. This creates the need for more precise quantitative metrics and measurements for energy management in the data center industry. However, despite the effort of multiple public and private agencies to address this problem, there is still little knowledge among practitioners on such topic.Aim. The goal of our work is to investigate the state-ofthe-Practice of power measurements and energy efficiency techniques in the data center industry.Method. We interviewed 7 practitioners and stakeholders from 4 companies of different size. We used semi-structured interviews of 1 hour as our research methodology.Results. Our results show that all the companies we interviewed measure power consumption, but only up to racklevel granularity. Several energy efficiency practices have been adopted, with positive results. However, the only metric considered to evaluate the impact of such practices is the Power Usage Effectiveness (PUE), although the representativity of such metric has been widely questioned in scientific literature and by our interviewees as well. We observed a lack of awareness with respect to other metrics, which could also be used to share such information across different stakeholders (e.g. suppliers, infrastructure managers, customers).Conclusions. Our contribution motivates further efforts from the data center industry to go beyond the PUE and adopt more advanced metrics to evaluate the energy efficiency of their data centers. This is a required step to ensure that real improvements are made towards sustainability goals.