1. A system for managing inactive states of computing devices comprising: a memory, a processor unit in communication with said memory, for performing a method comprising: receiving, at said processor unit, a request to one of: activate or deactivate one or more computing devices from a respective group of inactive or active computing devices, each said inactive or active computing device initially in a pre-determined state of readiness; activating or deactivating said one or more computing devices, said activating or deactivating resulting in a number of computing devices in one or more activation states of readiness i; computing an optimal configuration of said computing devices in said one or more said states of readiness i by minimizing an expected power consumption Σ i A i P i where i represents all inactive computing device states, A i represents a number of said computing devices currently in each state i, and, P i represents an average power consumption of a computing devices while in said state i; and placing said computing devices in said optimized configuration, said processor unit is further configured to: formulate an objective function to be minimized, said objective function representing said expected power consumption Σ i A i P i subject to a constraint, wherein, after one of said activating or deactivating one or more computing devices, said processor unit is further configured to: compute a resulting activation vector A′ representing said resulting number of computing devices in one or more activation states of readiness i, said optimizing including computing activation vector A″ representing a number of computing devices in said optimized one or more activation states of readiness i; wherein said objective function is subject to a constraint that R k ≦R 0 k for each computing devices k, wherein said R represents a readiness vector, a k th component R k representing a minimal amount of time fork computing devices to be restored to an active state given a specific activation vector A and a transition latency matrix T; and, R 0 represents a specified readiness vector, a k th component R 0 k representing a specified constraint on a maximum time permitted for k inactive servers to be restored to said active state.