Using Solid Metrics

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Using solid metrics
The most useful datacenter power-efficiency metric is the ratio of IT equipment load to total utility power:
Efficiency =IT Load/Total Facility Power
In a typical datacenter, this ratio is 0.3, meaning that only about 30 percent of the total utility draw actually powers servers. Another third of the power is used to remove the heat that servers generate. And roughly another third is consumed by power conversions in uninterruptible power supplies (UPS), power distribution units (PDUs), and miscellaneous power draws ranging from humidification to spot cooling systems.