CSR: Small: Cross-Layer Design of Power Delivery and Load Balancing for Green Data Centers

CSR：小型：绿色数据中心的电力传输和负载平衡的跨层设计

• 批准号: 1837924
• 负责人: Robert Pilawa-Podgurski
• 金额: $ 21.25万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-01-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1837924&HistoricalAwards=false
• 关键词: CSR; Small; Cross; Layer; Design

As ever more computing is moved to the cloud, the energy consumption of data centers becomes increasingly important, both from an environmental and cost viewpoint. As a result, there is an increasing trend towards reducing the energy and carbon foot- print of data centers. While there has been considerable efforts to reduce the energy consumption, relatively little attention has been paid towards the power delivery in data centers. The objective of this work is to reduce the high voltage conversion losses (currently contributing 10-15% power loss) to almost zero by designing a joint software and hardware power delivery architecture specifically for a multi-server environment. This research, which could lead to drastic reduction of power conversion losses in data centers, has far-reaching impact on the design of sustainable and green data centers. Participation of underrepresented groups is encouraged, and portions of the research is incorporated into cloud computing courses, as hardware projects into a laboratory power electronics course, and as a case study of data center power delivery in an advanced graduate level power electronics course. An interactive online power usage portal, that visualizes in real-time the power usage of each individual server in the test-cluster provides opportunities for public interaction with the research. These open-source software and hardware demonstrations enable practitioners from around the world to learn more about sustainable computing. This research explores a cross-layer design approach to data centers, where the power delivery architecture and software load balancing algorithms work together to achieve the highest possible power delivery efficiency. The research explores electrically series-connected racks of servers, to minimize overall power conversion and attendant losses. A key challenge in series voltage stacking is the variation in input voltage of each server due to imbalance of computational load in a series-stack. In this research, the challenge is addressed both in hardware and software. In software, scalable load balancing algorithms that ensure uniform power consumption in each server in the rack are developed. The load balancing algorithms simultaneously optimize for response time and power loss. Moreover, hardware power converters and distributed energy storage (e.g., capacitors, batteries) provide filtering and power balance in cases when software alone does not suffice. A key question being addressed is the suitable size of energy storage, and the required control bandwidth of the power converters to ensure proper operation for realistic workloads. In addition, high speed sensing and communication of electrical measurements of voltage and currents are employed in combination with operation of servers at asymmetric input voltages for static power consumption mismatch mitigation. The load balancing algorithms is tested with two types of workloads: (1) Interactive web workloads with short turnaround time and homogeneous servers; and (2) Map-reduce type workloads with long turnaround time and servers with data locality constraint.

一如既往的计算被移至云，从环境和成本观点来看，数据中心的能源消耗变得越来越重要。 结果，减少数据中心的能量和碳脚印刷的趋势越来越大。尽管已经做出了大量努力来减少能源消耗，但对数据中心的电力传递的关注很少。这项工作的目的是通过设计专门针对多服务器环境的联合软件和硬件电源架构来减少高压转换损耗（目前贡献10-15％的功率损失）几乎为零。 这项研究可能导致数据中心的功率转换损失急剧减少，对可持续和绿色数据中心的设计产生了深远的影响。鼓励代表性不足的群体的参与，并将部分研究纳入云计算课程中，将硬件项目作为实验室电力电子课程，以及作为高级研究生电源电力电子课程中数据中心动力传递的案例研究。一个交互式的在线功率使用门户网站，可实时可视化测试集群中每个服务器的功率使用情况，这为与研究的公共互动提供了机会。这些开源软件和硬件演示使来自世界各地的从业者能够了解有关可持续计算的更多信息。这项研究探索了针对数据中心的跨层设计方法，在该方法中，功率输送架构和软件负载平衡算法共同运行以达到最高的功率传递效率。该研究探索了电气连接的服务器机架，以最大程度地减少整体功率转换和随之而来的损失。串联电压堆叠中的一个关键挑战是，由于串联堆栈中计算负载的不平衡，每个服务器的输入电压的变化。在这项研究中，挑战在硬件和软件中都得到了应对。在软件中，开发了确保机架中每个服务器中均匀功耗的可扩展负载平衡算法。负载平衡算法同时优化响应时间和功率损失。此外，硬件电源转换器和分布式储能（例如，电容器，电池）在单独使用软件不足的情况下提供过滤和电源平衡。要解决的一个关键问题是储能的合适尺寸以及功率转换器所需的控制带宽，以确保适当的工作负载操作。此外，使用不对称输入电压在不对称输入电压下使用服务器运行的高速传感和电流的高速传感和通信，以用于静态功耗不匹配。 负载平衡算法通过两种类型的工作负载进行了测试：（1）交互式Web工作负载，其周转时间和均匀的服务器； （2）具有较长周转时间的MAP-REDUCE类型工作负载以及具有数据局部性约束的服务器。