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Matthew Garrett on the race to idle

Matthew Garrett on the race to idle

Posted May 10, 2008 10:37 UTC (Sat) by dlang (✭ supporter ✭, #313)
In reply to: Matthew Garrett on the race to idle by mjg59
Parent article: Matthew Garrett on the race to idle

if you aren't switching to a suspend mode when you hit the idle state, what is the benifit of
becoming idle?

you can blame it on whatever layers you want, but for the user the result is the same, in
practice the race-to-idle approach does not currently give a reasonable user experiance (in
many cases), and as a result, switching to a lower clock speed instead of race-to-idle is
actually better.


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Matthew Garrett on the race to idle

Posted May 10, 2008 10:53 UTC (Sat) by mjg59 (subscriber, #23239) [Link]

The benefit is that your CPU power draw drops to approximately nothing. On modern CPUs,
halving the speed of your processor doesn't halve its power draw. Letting it idle takes it
down to 0-1 watts.

Matthew Garrett on the race to idle

Posted May 11, 2008 11:23 UTC (Sun) by IkeTo (subscriber, #2122) [Link]

> On modern CPUs, halving the speed of your processor doesn't halve its power draw.

Hm... I read otherwise somewhere else, if you count only the power of the CPU.  (Actually it
should save more than half of its power, otherwise why slowing down?)  Would you mind sharing
with us where you get this idea?

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