Power/Energy quantification. A server farm has most of its servers operating at

only 50% capacity. The problem is that the power draw from these servers does not scale

linearly with the reduced load; that is, when the servers are operating at 50% capacity, they

consume 85% of maximum power. The server farm is considering an alternative of turning

the servers off, but they would take too long to restart in response to more load. A new

system has been proposed, which can be put in a “barely alive” state and allow for a quick

restart. The new servers require 20% of the maximum power while in this “barely alive” state.

a. How much power savings would be achieved by turning off 50% of the servers?

b. How much power savings would be achieved by placing 50% of the servers in the “barely

alive” state?

c. How much power savings would be achieved by reducing the voltage by 25% and

frequency by 40%?

d. How much power savings would be achieved by placing 25% of the servers in the “barely

alive” state and 25% off?