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Cc: freebsd-current@freebsd.org
Subject: Disabling CPUs at boot (was: Re: CPU hotplug)
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On Tue, 7 Apr 2009, 崔岩ccuiyyan@sina.com wrote:

>       Are there any methods to control the number of CPUs online or CPU 
> hotplug in FreeBSD?
>
> I want to shutdown some CPUs in the experiments.

Hi Yah:

Currently, we really only support fully disabling CPUs at boot-time by forcing 
the CPU's local APIC not to probe:

   hint.lapic.X.disabled=1

Replace X with the CPU ID, I believe.  And don't apply it to the boot 
processor. :-)

Robert N M Watson
Computer Laboratory
University of Cambridge
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