Re: Attempted summary of suspend-blockers LKML thread, take three

From: Arjan van de Ven
Date: Sat Aug 14 2010 - 12:53:39 EST


On Sat, 14 Aug 2010 08:10:48 -0700
"Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> wrote:
>
> So once you are down to one CPU, the last CPU shuts the system off,
> itself included? Or does the last CPU "run" in a deep idle state
> throughout suspend? (My guess is the former, and I am also curious
> whether the cache SRAMs are powered off, etc. But figured I should
> ask rather than guessing.)

they tend to go "off".

however I think you're making an assumption that there is a
real difference between a deep idle state and "off"....

For modern x86 hardware, that assumption isn't really valid.
(other than a very very small sram that stores register content in the
idle case)



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Arjan van de Ven Intel Open Source Technology Centre
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