1. A machine implemented method comprising: determining a state of an instruction queue of a subsystem of a data processing system; and sending a message about the state of the instruction queue to a processing unit of the data processing system in order to cause power to be reduced in the subsystem, wherein power is reduced when the state of the instruction queue has instructions for only future events or actions, wherein time values of the future events or actions scheduled to be performed by the subsystem are adjusted at run-time by a latency value based on a power-up latency associated with the subsystem.