Power Model Focus

Energy E
$P = P_{switching} + P_{static}$
Dynamic Power $P_{switching} = \alpha f C_L V_{DD}^2$ $P_{s w i t c hin g} = α f C_{L} V_{DD}^{2}$
- Switching and Short-circuit power $E= P t = \alpha f C_L V_{DD}^2 t = \alpha C_L V_{DD}^2 \propto \alpha C_L f^2$
As $V\propto f$ $V \propto f$ for the last step.
Leakage power $P_{static} = V_{DD} I_{Leakage}$ $P_{s t a t i c} = V_{DD} I_{L e aka g e}$ = $\beta$ $β$
- Current that flows through the transistor when there is no activity.
- Refresh power
- Standby power
- For instance, in DRAM (widely used as main memory), leakage power can be as much as 10 times of the dynamic read/write power on the memory chip using a process technology with the size smaller than 50nm (Wilton and Jouppi 1996)
Load
Performance: Deadline-aware, Fairness
Shared Memory / Resource Contention
- DRAM
- Cache
Complexity
- O(1), O(n)