Cloud providers are adapting datacenter (DC) capacity to reduce carbon emissions. With hyperscale datacenters exceeding 100 MW individually, and in some grids exceeding 15% of power load, DC adaptation is large enough to harm power grid dynamics, increasing carbon emissions, power prices, or reduce grid reliability. To avoid harm, we explore coordination of DC capacity change varying scope in space and time. In space, coordination scope spans a single datacenter, a group of datacenters, and datacenters with the grid. In time, scope ranges from online to day-ahead. We also consider what DC and grid information is used (e.g. real-time and day-ahead average carbon, power price, and compute backlog). For example, in our proposed PlanShare scheme, each datacenter uses day-ahead information to create a capacity plan and shares it, allowing global grid optimization (over all loads, over entire day). We evaluate DC carbon emissions reduction. Results show that local coordination scope fails to reduce carbon emissions significantly (3.2%–5.4% reduction). Expanding coordination scope to a set of datacenters improves slightly (4.9%–7.3%). PlanShare, with grid-wide coordination and full-day capacity planning, performs the best. PlanShare reduces DC emissions by 11.6%–12.6%, 1.56x–1.26x better than the best local, online approach’s results. PlanShare also achieves lower cost. We expect these advantages to increase as renewable generation in power grids increases. Further, a known full-day DC capacity plan provides a stable target for DC resource management.
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Beyond PUE: Flexible Datacenters Empowering the Cloud to Decarbonize
Traditional datacenter design and optimization for TCO and PUE is based on static views of power grids as well as computational loads. Power grids exhibit increasingly variable price and carbon-emissions, becoming more so as government initiatives drive further decarbonization. The resulting opportunities require dynamic, temporal metrics (eg. not simple averages), flexible systems and intelligent adaptive control. Two research areas represent new opportunities to reduce both carbon and cost in this world of variable power, carbon, and price. First, the design and optimization of flexible datacenters. Second, cloud resource, power, and application management for variable-capacity datacenters. For each, we describe the challenges and potential benefits.
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- PAR ID:
- 10400420
- Date Published:
- Journal Name:
- USENIX Hot Carbon
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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