1. A computer-implemented method for managing a power usage of a computing device, the method comprising: receiving a first set of executable instructions to perform a first task on a computer of a plurality of computers; determining whether an expected amount of power used by the computer to execute the first set of executable instructions to perform the first task will exceed a desired power budget; based on the determination that the expected amount of power to execute the first set of executable instructions will exceed the desired power budget, modifying the first set of executable instructions; executing the modified first set of executable instructions at the computer to perform the first task, wherein the computer uses a first actual amount of power to execute the modified first set of executable instructions, and the first actual amount of power is different than the expected amount of power; comparing the first actual amount of power to the desired power budget; receiving a second set of executable instructions to perform a second task on the computer; and based on a variance between the first actual amount of power and the desired power budget, modifying the second set of executable instructions at the computer to perform the second task, wherein the computer uses a second actual amount of power to execute the modified second set of executable instructions, and the second actual amount of power is different than the first actual amount of power.