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From: "Pranav Peshwe" <pranavpeshwe@gmail.com>
To: <freebsd-questions@freebsd.org>
Date: Wed, 5 Oct 2005 23:18:59 +0530
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Subject: FreeBSD and Intel Hyperthreading technology.
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Hello,
            I have an Intel P4 2.8Ghz processor with Hyperthreading (HT).
The dmesg displays a message saying HT is present and 2 logical
CPUs present.I tried toggling the setting in BIOS but no difference.
    How does the FBSD(v5.4 stable) kernel deal with HT ? Do the internal
workings( maybe locking, per processor data or other things) change as 
compared to a simple non-HT processor ? or does it use employ SMP
methods to deal with the 2 logical CPUs presented by a HT processor ?

I want to do kernel programming on FBSD and my project partners have
non-HT CPUs.How much difference will HT make ? can it be avoided ?

TIA.

Regards,
Pranav Peshwe

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