enable smp / hyperthreading

Roland Smith rsmith at xs4all.nl
Mon Nov 7 19:06:02 GMT 2005

On Mon, Nov 07, 2005 at 07:53:20PM +0100, jwl at io.dk wrote:
> Hi
> I've just installed 6.0-RELASE and am trying to get SMP to work (I have af
> Pentium 4 with HT). So I've compiled the kernel with 'options SMP' and
> according to dmesg the two CPUs are found:
> FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs
>  cpu0 (BSP): APIC ID:  0
>  cpu1 (AP): APIC ID:  1
> But I'm not sure that both are enabled, because at this is at the end of
> dmesg and I dont see the other CPU being enabled somewhere:
> SMP: AP CPU #1 Launched!

I think it is referring to the Auxiliary Processor (AP), because the BSP
(don't know what that stands for, though) is obviously already active.
> According to 'sysctl -a' there are 2 CPUs, but only 1 active and SMP
> doesnt seem to be disabled:
> kern.smp.cpus: 2
> kern.smp.disabled: 0
> kern.smp.active: 1

  sysctl -d kern.smp.active
  kern.smp.active: Number of Auxillary Processors (APs) that were
  successfully started

This is the number of _extra_ CPUs, which chould be 1.
R.F.Smith (http://www.xs4all.nl/~rsmith/) Please send e-mail as plain text.
public key: http://www.xs4all.nl/~rsmith/pubkey.txt
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