Program Execution Speed
The speed at which a digital circuit can switch states - that is, to go from "low" (VSS) to "high" (VDD) or vice versa - is proportional to the voltage differential in that circuit. Reducing the voltage means that circuits switch slower, reducing the maximum frequency at which that circuit can run. This, in turn, reduces the rate at which program instructions that can be issued, which may increase run time for program segments which are sufficiently CPU-bound.
This again highlights why dynamic voltage scaling is generally done in conjunction with dynamic frequency scaling, at least for CPUs. There are complex tradeoffs to consider, which depend on the particular system, the load presented to it, and power management goals. When quick responses are needed, clocks and voltages might be raised together. Otherwise, they may both be kept low to maximize battery life.
Read more about this topic: Dynamic Voltage Scaling
Famous quotes containing the words program, execution and/or speed:
““Hear me,” he said to the white commander. “I am tired. My heart is sick and sad. Our chiefs are dead; the little children are freezing. My people have no blankets, no food. From where the sun stands, I will fight no more forever.””
—For the State of Montana, U.S. public relief program (1935-1943)
“My weakness has always been to prefer the large intention of an unskilful artist to the trivial intention of an accomplished one: in other words, I am more interested in the high ideas of a feeble executant than in the high execution of a feeble thinker.”
—Thomas Hardy (1840–1928)
“It was undoubtedly the feeling of exile—that sensation of a void within which never left us, that irrational longing to hark back to the past or else to speed up the march of time, and those keen shafts of memory that stung like fire.”
—Albert Camus (1913–1960)