Optimizing Software Applications for Power: Part 6 (of 13)

Part 6: Reducing Computation

As simple as it sounds, a key strategy for reducing application power requirements is to do less computation. With respect to the ACPI framework described above, such reductions have the effect of increasing system idleness and hence OS opportunities for applying power-saving C-states. Reducing computation also decreases processor utilization which allows the OS to more aggressively apply P-states that trade power savings for performance when the latter is less needed.

But how does one reduce computation? The good news here is that all we have learned about performance optimization over the last 40+ years of computing applies! A few illustrations to follow.

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