Metrics are used in order for data centres to measure IT performance and improve on problem areas. The metrics range from granular technical information, which is used by data centre staff, to key performance efficiency indicators that inform the business groups relying on the data centre.
The importance of data centre metrics has risen to extreme importance over the past years, which has led to the emergence of different types of metrics.
The Green Grid, however, recently released a warning as IT leaders with data centre responsibilities are using a range of metrics which are too narrow or have not deployed the necessary tools to get the required detail of measurement in order to drive efficiency.
Based on this, CBR put together a list of the top five metrics, developed by The Green Grid, which support data centre efficiency.
Power Usage Effectiveness (PUE)
Created by The Green Grid, PUE is considered as the ratio of total facilities energy to IT equipment energy. It has also been identified as one of the best metrics available to determine a data centre’s energy efficiency.
PUE is able to determine opportunities to improve a data centre’s operational efficiency, how a data centre compares with its competitors, if the data centre operators are improving the designs and processes over time and also reveals opportunities to repurpose energy for additional IT equipment.
This metric makes clear focus of the total facility power and IT equipment power, with cooling being one of its major players in PUE measurement.
Performance Indicator (PI)
In continuation of the PUE, The Performance Indicator is a set of metrics combined, also developed by The Green Grid.
PI is used for assessing data centre power and cooling effectiveness, whereby operators can use it to evaluate the cooling performance of their data centre, also predicting the future thermal states.
The three metrics which are included in PI measurements are PUE ratio, IT Thermal Conformance, IT Thermal Resilience.
It measures each of these metrics individually, then determining how a change in one metric affects the others.
Data Centre Infrastructure Efficiency (DCiE)
The DCiE is a metric used to determine the energy efficiency of a data centre. It is calculated by dividing IT equipment power by total facility power.
Considered as the inverse of PUE, it is located within IT devices, calculating the total output of the data centre.
Water Usage Effectiveness (WUE)
WUE is a site-based metric that assesses the amount of water used on-site for operation of the data centre. This includes measurements of water used for humidification and water evaporated on-site for energy production or cooling of the data centre and its support systems.
In order to determine the source energy water usage, the facility’s total energy must be known.
It also includes a source-based metric which includes water used on-site and water used off-site in the production of the energy used on-site.
Carbon Usage Effectiveness (CUE)
The CUE metric is used to describe the sustainable use of electrical energy in a data centre.
In terms of the calculation of measurements, the most efficient approach is to multiply the carbon emission factor by the data centre’s annual PUE.
CUE is a source-based metric, and even with its on-site generation, that generation is the source of the energy.
