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Date:      Wed, 22 Oct 2003 23:09:58 -0400
From:      Gerald Freymann <>
Subject:   Re: Multiple CPUs...verifying
Message-ID:  <>
In-Reply-To: <000001c3990d$2c0bc7e0$f6c8a8c0@pepstep>
References:  <000001c3990d$2c0bc7e0$f6c8a8c0@pepstep>

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On Wed, 22 Oct 2003 22:27:13 -0400
"Marco Greene (Home)" <> wrote:

|O|>Does FreeBSD autodetect multiple CPU's or do you specifically have to
|O|>configure the kernel and recompile?

 In my experiences with FreeBSD 4-4.8R, you have to uncomment two lines in
the kernel config file.

# To make an SMP kernel, the next two are needed
options        SMP                     # Symmetric MultiProcessor Kernel
options        APIC_IO                 # Symmetric (APIC) I/O

 and then rebuildworld and kernel. 

 World because there are programs that will compile differently if there
are multiple CPU's (at least I think that's right!)

 Kernel for obvious reason.

|O|>outline in the handbook.  However, when I try to boot with the new
|O|> doesn't work.

 I think you're going to have to give more information than "it doesn't
work" if you expect anybody to attempt to offer advice.

|O|>Also, how do you verify whether or not both CPUs have been configured
|O|>in the kernel...and that they are in fact being used?

 type:   dmesg |more

 and look through the results. When my dual-cpu loads up, I see where
there 2nd CPU is acknowledged. Even doing a 'top' shows me which CPU is in
use for each program.

 Scary Gerry -- Senior Systems Manager
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