How much is wasted.
WHAT THE STANDARD MEASURE IS
Total facility power divided by power delivered to equipment.
WHAT THAT EXPRESSES
How much is consumed by everything other than the computing itself.
WHAT A PERFECT FIGURE WOULD BE
One, meaning no overhead at all, which is unachievable.
WHAT CONSUMES THE OVERHEAD
Cooling, mostly Power conversion losses Lighting and everything else
WHY IT MATTERS
Energy is a major operating cost, and in many places a major constraint.
WHAT IMPROVES IT
Containment, preventing air mixing Higher operating temperatures, within equipment tolerances Efficient cooling design Modern power equipment
WHAT TO BE CAREFUL WITH
Comparing figures between facilities in different climates Figures measured at favourable times
WHAT TO ASK
How and when the figure was measured.
WHAT ELSE TO CONSIDER
Efficiency of your own equipment.
WHAT TO DO
Remove equipment that is no longer used.
WHY
Idle servers consume substantial power and cooling for nothing.