SMP only detects one CPU - help?

Apatewna apatewna at
Fri Apr 20 17:12:00 UTC 2007

O/H Adam J Richardson έγραψε:
> Hi all,
> Firstly, apologies for the length of this. It's my first mailing list 
> posting, so I hope I'm not breaching any etiquette codes. Also I've only 
> been using FreeBSD for a couple of years, so I'm still very new to the 
> system.

Maybe you should use FreeBSD more often :)

> I have recently become the proud owner of a second-hand HP NetServer 
> e800, which has two Pentium-III class [686] CPUs in it. I've installed 
> 6.2-RELEASE-p3 [which is also referred to as 6.2-STABLE, is that 
> correct?] and built myself a SMP kernel. I'm sure it's a SMP kernel, 
> because the config file has "options SMP" in it and while running it 
> "sysctl kern.smp.maxcpus" returns 16. The BIOS says there are two CPUs, 
> so I guess the second CPU is in fine condition and ready to go.

As of FreeBSD 6.2 RELEASE, SMP systems are correctly detected and the 
SMP kernel is used, no need to rebuild kernel. I have such an old 
hardware arround (Dual P3 at 500) and 6.2 RELEASE loaded the SMP kernel as 
expected. Same thing on shiny new Core2Duo machines.

Try a reinstall, if this a testing machine and you'll notice that the 
SMP kernel is loaded by default, unless some other strange hardware 
problem exists.

RTFM and STFW before anything bad happens
Thanos Rizoulis
Electronic Computing Systems Engineer
Larissa, Greece
FreeBSD/PCBSD user

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