Running on only some cores

Astrodog astrodog at
Tue Jan 20 05:56:13 PST 2009

You can set MAXCPU in the kernel config, if nothing else...

On Tue, Jan 20, 2009 at 6:27 AM, Barney Cordoba
<barney_cordoba at> wrote:
> --- On Tue, 1/20/09, Christoph Mallon <christoph.mallon at> wrote:
>> From: Christoph Mallon <christoph.mallon at>
>> Subject: Re: Running on only some cores
>> To: barney_cordoba at
>> Cc: freebsd-current at
>> Date: Tuesday, January 20, 2009, 6:25 AM
>> Barney Cordoba schrieb:
>> > Can FreeBSD be configured to only run on N cores? So
>> for example, if I have an 8 core system, can it be
>> configured in loader.conf or through a simple hack to only
>> run on 2 cores?
>> >
>> > We're testing various configs, and its not
>> terribly convenient to keep swapping out CPUs.
>> man 4 smp
>> look for machdep.hlt_cpus
> Ok, I see this does something when run after boot. So there is no way to get the OS to simply not launch the CPU? We have something that reads the number of cpus, which doesn't seem to change.
> Barney
> _______________________________________________
> freebsd-current at mailing list
> To unsubscribe, send any mail to "freebsd-current-unsubscribe at"

"A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects."
--- Robert A. Heinlein

More information about the freebsd-current mailing list