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Date: Fri, 10 Oct 2003 06:00:26 -0500 (CDT)
From: Mike Silbersack <silby@silby.com>
To: Joseph Koshy <jkoshy@FreeBSD.ORG>
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cc: freebsd-hackers@freebsd.org
Subject: Re: Determining CPU features / cache organization from userland
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On Fri, 10 Oct 2003, Joseph Koshy wrote:

> Hi -hackers,
>
> I'm looking for ways that a userland program can determine the CPU
> features available on an SMP machine -- processor model, stepping
> numbers, supported features, cache organization etc.
>
> For example, on some x86 processors the CPUID instruction could be
> used to determine some of these parameters, but using this instruction
> in an SMP context is a little tricky since we do not know which CPU
> gets to execute the instruction.

At least in the Intel world, multiprocessor systems are _always_ supposed
to have matching processor steppings, so the reliability of the
information should be very good indeed.

Mike "Silby" Silbersack