Gain More from PUE: Assessing Data Center Infrastructure Power Adaptability

The power usage effectiveness (PUE) for data centers is used by operators as KPI to measure the absolute infrastructure power overhead. However, this only draws conclusions on static or average operation conditions during an usual annual time period. For analyzing the aspect of dynamics in the IT to infrastructure power relation, we propose two new metrics. First, the power variability (PVar). It simply indicates the relative rates and heights of power variations. Second, the infrastructure power adaptability (IPA). It relates the power variabilities and relative average deviations of IT and infrastructure power in order to represent the scalability and adaptability of the infrastructure to the IT demands. Both metrics use the same input data also needed for a continuous PUE calculation. Thus, the applicability in a data center running a PUE-metering can be ensured. In an evaluation, we applied the IPA on power traces of a container data center (in the following denoted as CDC) and compared the results with PUE scalability, a metric with the same scope. The comparison showed, that IPA covers more operating states and is therefore more robust and reliable than its counterpart.