Re: PROBLEM: Celeron Core

From: Tomasz Chmielewski
Date: Sun Jan 20 2008 - 17:06:33 EST


Clock throttling is not likely to save your battery, unless you have tasks that are running at 100% CPU for an unlimited time or something, and you force your CPU to throttle. Normally most people have tasks that run and then the CPU idles - loading an email, displaying a web page, etc. Clock throttling will just make these tasks utilize the CPU for a longer time proportional to the amount clock throttling and therefore negate any gains in battery usage.

Aren't you forgetting about CPUfreq governors? Which mean: use the maximum CPU frequency when the system is busy, throttle down (or lower voltage) when the system is idle.

So yes, throttling will save the battery.

Besides, not all CPUs support power management (voltage control).


IMO clock throttling (as opposed to the reduction of the frequency of an idle
CPU) is only useful for preventing the CPU from overheating.

And for reducing power on CPUs that can't do any power management, just throttling.

For example, a server that doesn't crunch any numbers at night will certainly use less power when throttled.


--
Tomasz Chmielewski
http://wpkg.org


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