Outline Break-even time(B) Next Device Usage Time(NDUT(t)) Conservative Energy-Efficient Device Scheduling(CEEDS) Device Forbidden Region(DFR) Feasibility Dynamic Power Management(DPM) through Device Forbidden Regions Comparison Conclusion
Break-even time : The power consumption in active state : The power consumption in sleep state : The time overhead to perform a transition from active to sleep state : The time overhead to perform a transition from sleep to active state : The energy overhead to perform a transition from active to sleep state : The energy overhead to perform a transition from sleep to active state : The break-even time of the device
Next Device Usage Time(NDUT(t)) Prediction Current time(t) Tasks in ready queue Release time of jobs that request Current tNDUT(t) Task use
Device Forbidden Region(DFR) Rat-Monotonic scheduling(RMS). Duration Period Expected Energy Savings(EES) of
Feasibility Time demand function of Corollary : A set of periodic tasks can be feasibly scheduled by DFR-RMS if i t 0 t Ti,
DPM through Device Forbidden Regions
Comparison Always on (AON) --Where the devices remain in active state throughout the simulation (no dynamic power management). CEEDS --Adapted to RMS settings. This scheme performs device shutdown and activation based solely on next device usage time predictions. DER-RMS
Conclusion Compare with original CEES, no matter with DVS or without DVS, RMS-DFR can save up to 27% energy consumption, under the worst condition, it can also save 20% consumption.