LiteGreen: Saving Energy in Networked Desktops Using Virtualization

Tathagata Das tathadas@microsof t.com Microsoft Research India Pradeep Padala∗ Venkata N. Padmanabhan ppadala@docomolabs-usa.com padmanab@microsof t.com DOCOMO USA Labs Microsoft Research India Kang G. Shin kgshin@eecs.umich.edu The University of Michigan U.S. Of this, 65 TWh/year is consumed by PCs in enterprises, which constitutes 5% of the commercial building electricity consumption in the U.S. Moreover, market projections suggest that PCs will continue to be the dominant desktop computing platform, with over 125 million units shipping each year from 2009 through 2013 [15]. The usual approach to reducing PC energy wastage is to put computers to sleep when they are idle. However, the presence of the user makes this particularly challenging in a desktop computing environment. Users care about preserving long-running network connections (e.g., login sessions, IM presence, file sharing), background computation (e.g., syncing and automatic filing of new emails), and keeping their machine reachable even while it is idle. Putting a desktop PC to sleep is likely to cause disruption (e.g., broken connections), thereby having a negative impact on the user, who might then choose to disable the energy savings mechanism altogether. To reduce user disruption while still allowing machines to sleep, one approach has been to have a proxy on the network for a machine that is asleep [33]. However, this approach suffers from an inherent tradeoff between functionality and complexity because of the need for application-specific customization. In this paper, we present LiteGreen, a system to save desktop energy by employing a novel approach to minimizing user disruption and avoiding the complexity of application-specific customization. The basic idea is to virtualize the user’s desktop computing environment, by