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From: Jeff Sipek <jeffpc@optonline.net>
To: Hans Kristian Rosbach <hk@isphuset.no>
Cc: linux-kernel@vger.kernel.org
Subject: Re: SMP cpu deep sleep
Date: Fri, 20 Aug 2004 04:58:29 -0400	[thread overview]
Message-ID: <200408200458.38591.jeffpc@optonline.net> (raw)
In-Reply-To: <1092989207.18275.14.camel@linux.local>

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On Friday 20 August 2004 04:06, Hans Kristian Rosbach wrote:
> While reading through hotplug and speedstep patches
> I came to think of a feature I think might be useful.
>
> In an SMP system there are several cpus, this generates
> extra heat and power consuption even on idle load.
> Is there a way to put all cpus but cpu1 into a kind of
> deep sleep? Cpu1 would have to do all work (including irqs)
> of course.

With Rusty's Hotplug CPU, a userspace script should be able to do this by 
cat'ing 1 or 0 into the appropriate sysfs file.

Jeff.

- -- 
"If I have trouble installing Linux, something is wrong. Very wrong."
  - Linus Torvalds
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  reply	other threads:[~2004-08-20  9:02 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-08-20  8:06 SMP cpu deep sleep Hans Kristian Rosbach
2004-08-20  8:58 ` Jeff Sipek [this message]
2004-08-20  9:42   ` Hans Kristian Rosbach
2004-08-20 14:38     ` Zwane Mwaikambo
2004-08-20 16:44 ` Wes Felter
2004-08-21  0:53   ` Benjamin Herrenschmidt
2004-08-23 21:30   ` Bill Davidsen
2004-08-28 19:15     ` Alan Cox
2004-08-24 22:48   ` Pavel Machek
  -- strict thread matches above, loose matches on Subject: below --
2004-08-20 14:30 Nakajima, Jun

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