CAREER: Energy-Efficient Datacenters with Wireless Interconnection Networks

“CAREER：具有无线互连网络的节能数据中心”项目的主要目标是通过集成芯片内和芯片间的无线网络来建立无线数据中心的设计原则。世界各地的计算机器消耗的能源数量惊人。据《纽约时报》2012年9月报道，像数据中心这样的数字仓库使用300亿瓦的电力，相当于30座核电站的发电量。网络计算元素在所有的计算机器中都无处不在，比如数据中心、服务器和高性能计算（HPC）。成千上万的多核芯片相互连接，形成一个完整的数据中心，使得网络在整个系统的性能和能源效率中发挥着至关重要的作用。在大型计算机器中，不同芯片的核心或内存组件之间的数据传输需要在网络的不同层次上遍历各种互连技术，通常需要更改交换协议，从而导致开销。更重要的是，根据国际半导体技术路线图（ITRS），片间互连的间距没有片上互连的间距那么快，导致未来的性能差距。此外，片上和片外互连的布线复杂性会带来设计挑战、串扰和信号完整性问题，从而加剧了这一问题。最近的研究设想使用毫米波（mm-wave）技术来设计片上网络的片上无线互连，与传统架构相比，它显着更节能。另一方面，近年来已经进行了相当多的研究，以开发使用相同的60GHz免许可无线频谱的无线数据中心。本工作中提出的集成架构将能够在数据中心的通信处理核心之间建立无线路由。这个高度跨学科的项目将吸引来自学术界和工业界的计算机工程、计算机科学和电子工程等学科的专家。利用计算机架构、通信、集成电路封装和数据中心等各个领域的概念和技术，该项目将建立大型计算仓库的无线互连方法，以减少其能源消耗和碳足迹，最终形成绿色和可持续的计算范式。

The principal aim of this CAREER: Energy-Efficient Datacenters with Wireless Interconnection Networks project is to establish design principals of a wireless datacenter by integrating intra- and inter-chip wireless networks. Computing machinery around the world consumes staggering amounts of energy. According to the NY Times in September 2012, digital warehouses like datacenters use thirty billion watts of electricity, which is equivalent to the output of thirty nuclear power plants. Networked computing elements are omnipresent in all computing machinery like datacenters, servers and High Performance Computing (HPC). Tens to thousands of multicore chips are interconnected to form an entire datacenter making the role of the network paramount in the performance and energy efficiency of the entire system. Data transfer between cores or memory components in different chips in large computing machinery need to traverse various interconnection technologies at the different levels of the network, often requiring change of switching protocols thus resulting in overheads. More importantly, according to the International Technology Roadmap for Semiconductors (ITRS), the pitch of the interchip interconnects is not scaling as fast as the pitch of on-chip interconnects, resulting in a performance gap in the future. Additionally, the wiring complexity of both on-chip and off-chip interconnects exacerbates the problem by posing design challenges, crosstalk and signal integrity issues. Recent research envisions on-chip wireless interconnects using millimeter-wave (mm-wave) technologies for designing Network-on-Chips, which are significantly more energy-efficient compared to traditional architectures. On the other hand in recent years considerable research has been done to develop wireless datacenters using the same 60GHz unlicensed wireless spectrum. The integrated architecture proposed in this work will be capable of establishing wireless routes between communicating processing cores in a datacenter. This highly interdisciplinary project will engage experts from the disciplines of computer engineering, computer science and electrical engineering from both academia and industry. Using concepts and technologies from various domains like computer architecture, communication, integrated circuit packaging and datacenters, the project will establish methodologies for wireless interconnections in large-scale computing warehouses to decrease their energy consumption and carbon footprint, ultimately resulting in a green and sustainable computing paradigm.