GreenColo: Incentivizing Tenants for Reducing Carbon Footprint in Colocation Data Centers

The massive energy consumption of data centers worldwide has resulted in a large carbon footprint, raising serious concerns to sustainable IT initiatives and attracting a great amount of research attention. Nonetheless, the current efforts to date, despite encouraging, have been primarily centered around owner-operated data centers (e.g., Google data center), leaving out another major segment of data center industry — colocation data centers — much less explored. As a major hindrance to carbon efficiency, colocation suffers from “split incentive”: tenants are often charged based on their peak power subscription regardless of their actual energy consumption, and hence they may not be willing to manage their servers for carbon efficiency. In this paper, we aim at minimizing the carbon footprint of geo-distributed colocation data centers, while ensuring that the operator’s cost meets a long-term budget constraint. We overcome the “split incentive” hurdle by devising a novel online incentive mechanism, called GreenColo, in which tenants voluntarily bid for energy reduction at self-determined prices and will receive financial rewards if their bids are accepted at runtime. Using trace based simulation we show that GreenColo results in a carbon footprint fairly close (23% vs 18%) to the optimal offline solution with future information, while being able to satisfy the colocation operator’s long-term budget constraint. We demonstrate the effectiveness of GreenColo in practical scenarios via both simulation studies and scaleddown prototype experiments. Our results show that GreenColo can reduce the carbon footprint by up to 24% without incurring any additional cost for the colocation operator (compared to the no-incentive baseline case), while tenants receive financial rewards for “free” without violating service level agreement.