Virtualization And Cloud Computing: Optimized Power, Cooling, And Management Maximizes Benefits

By Suzanne Niles and Patrick Donovan, senior research analysts, Schneider Electric's Data Center Science Center

Without question, IT virtualization - the abstraction of physical network, server, and storage resources - has greatly increased the ability to utilize and scale compute power. Indeed, virtualization has become the very technology engine behind cloud computing itself. While the benefits of this technology and service delivery model are well known, understood, and increasingly being taken advantage of, their effects on the data center physical infrastructure (DCPI) are less understood. The purpose of this paper is to describe these effects while offering possible solutions or methods for dealing with them.

These effects are largely not new and successful strategies for dealing with them exist today. There are four effects or attributes of IT virtualization that will be covered in this paper.

1. The rise of high density– Higher power density is likely to result from virtualization, at least in some racks. Areas of high density can pose cooling challenges that, if left unaddressed, could threaten the reliability of the overall data center.
2. Reduced IT load can affect PUE– After virtualization, the data center's power usage effectiveness (PUE) is likely to worsen. This is despite the fact that the initial physical server consolidation results in lower overall energy use. If the power and cooling infrastructure is not right-sized to the new lower overall load, physical infrastructure efficiency measured as PUE will degrade.
3. Dynamic IT loads – Virtualized IT loads, particularly in a highly virtualized, cloud data center, can vary in both time AND location. In order to ensure availability in such a system, it's critical that rack-level power and cooling health be considered before changes are made.
4. Lower redundancy requirements are possible– A highly virtualized data center designed and operated with a high level of IT fault-tolerance may reduce the necessity for redundancy in the physical infrastructure. This effect could have a significantly positive impact on data center planning and capital costs.

This paper approaches these effects in the context of a highly virtualized environment typical of a cloud-based data center with dynamic demand requirements. The list of white papers at the end provides additional general and detailed information about these topics in the overall data center context, virtualized or not.