Also seeing 2 x quad-core system slower that 2 x dual core

Kris Kennaway kris at
Fri Nov 30 08:15:00 PST 2007

Ivan Voras wrote:
> Kris Kennaway wrote:
>> Check dmesg for the APIC numbers corresponding to the CPUs you want to
>> disable and add the corresponding entries to /boot/loader.conf, e.g.:
>> hint.lapic.1.disable="1"
>> hint.lapic.3.disable="1"
>> hint.lapic.5.disable="1"
>> hint.lapic.7.disable="1"
> Hi,
> Do you know how his method compares to setting machdep.hlt_cpus ?

That is not supported with ULE (and will lead to deadlocks), but I don't 
know off-hand if hyperthreading virtual CPUs have their own apic...ok, 
it does on one of my systems at least, so that is probably the way to go 
when possible.


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