Server farms such as Google and Yahoo! provide enough compute capacity for the highest request rate of the day. Imagine that mos
t of the time these servers operate at only 60% capacity. Assume further that the power does not scale linearly with the load; that is, when the servers are operating at 60% capacity, they consume 90% of maximum power. The servers could be turned off, but they would take too long to restart in response to more load. A new system has been proposed that allows for a quick restart but requires 20% of the maximum power while in this "barely alive" state. a. How much power savings would be achieved by turning off 60% of the servers? b. How much power savings would be achieved by placing 60% of the servers in the "barely alive" state? c. How much power savings would be achieved by reducing the voltage by 20% and frequency by 40%? d. How much power savings would be achieved by placing 30% of the servers in the "barely alive" state and 30% off?