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Subject: Re: Linux 2.4.19-rc1-ac3
From: Thomas Sailer <sailer@scs.ch>
To: Russell King <rmk@arm.linux.org.uk>
Cc: Linux Kernel <linux-kernel@vger.kernel.org>
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On Sat, 2002-07-13 at 21:54, Russell King wrote:

> You're right if your CPU usage is 100% - lowering the CPU clock rate
> means you take longer to complete the task, and with the static
> element of the CPU power consumption, you'd probably end up using
> more energy to perform the same task in a longer time.

The point is that frequency scaling is normally used with voltage
scaling. And lowering the voltage decreases the maximum frequency
roughly linearly, while the dynamic power consumption decreases
quadratically with voltage.

Tom

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