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From: Hans Kristian Rosbach <hk@isphuset.no>
To: linux-kernel@vger.kernel.org
Subject: SMP cpu deep sleep
Date: Fri, 20 Aug 2004 10:06:47 +0200	[thread overview]
Message-ID: <1092989207.18275.14.camel@linux.local> (raw)

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.

We have a lot of SMP systems that we host, and they
are heavily used ~10 hours of the day, the rest they are
mostly idle. They could run on only 1 cpu during lenghty
idle periods.

If it is possible to put cpus to a deeper sleep than
just the simple idle, then the kernel could make use of this.

It would be a cool feature.

Sincerly
    Hans K. Rosbach



             reply	other threads:[~2004-08-20  8:09 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-08-20  8:06 Hans Kristian Rosbach [this message]
2004-08-20  8:58 ` SMP cpu deep sleep Jeff Sipek
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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