Dynamic rack power provision to optimize rack power performance

Large data centers consume huge electricity every year. The power constraint is key factor for data center operator to increase rack server density, meanwhile a lot of provisioned power is reserved as the safe margin to handle the rarely peak power demand or power source failure, leading to considerable power under-utilization as well as implicated performance loss comparing to design target. This paper studied the problem of rack power utilization from internet data centers and analyzed approaches to optimize rack power utilization for the rack equipped with rack wide battery backup system. The dynamic rack power provision (DRPP) is proposed to address rack power under-utilization problem without expanding rack power capacity and an autonomous power control algorithm is discussed. By using power capacity locked in battery backup system to handle the sporadic power spike, the dynamic rack power provision is able to provision more servers into the rack by keeping no change of rack power budget. At last, this paper discussed the evaluation methodology and presented the experimental results, covering density improvement, performance impacts, and battery capability. The results showed 15%-25% utilization improvement for the experimental cloud workloads with the method proposed by this paper.