Data centers concern not just energy usage, but also other important overall considerations such as the actual computational work, the energy efficiency and the performance of servers. The server, as one of the key ingredients of a data center, plays an increasingly crucial role in contributing to the overall energy use, especially in cases where the efficiency of the infrastructure has been optimized. Baidu has been exploring the sweet zone between power and performance in efficient rack server design and deployment for their self-built data center energy efficiency optimization from all the aspects. Recent deployment of rack server with distributed backup battery (Li-ion) subsystem (BBS) is one typical example to demonstrate their advanced rack server design for energy efficiency. Compared with lead acid battery based traditional UPS in data center, distributed BBS design in Baidu rack server has an advantage in lower power loss, data center power delivery and topology simplification, data center real estate saving, scalable deployment on demand without overprovision and so on, which overall contributes to a total cost ownership (TCO) reduction on both cap-ex (i.e., power infrastructure investment) and op-ex (i.e., electricity bill).
This paper introduces overall architecture and design of Baidu rack server with distributed BBS. Furthermore details energy efficiency design methodology of power peak draw trimming based on workload power characterization; Also the related lab data collection, experiments result, ongoing work and future plan are summarized in the end. This paper also recaps TCO saving points benefiting from distributed BBS design into rack server system.