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Date:      Wed, 25 Apr 2007 16:08:06 +0200 (CEST)
From:      Oliver Fromme <olli@lurza.secnetix.de>
To:        freebsd-stable@FreeBSD.ORG, tarkhil@webmail.sub.ru
Subject:   Re: 6.2-RELEASE does not use second CPU on pentium D
Message-ID:  <200704251408.l3PE86XV059658@lurza.secnetix.de>
In-Reply-To: <462F15B4.4010201@webmail.sub.ru>

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Alex Povolotsky wrote:
 > I have a Pentium D box, running 6.2-RELEASE. In dmesg, I see CPU#1 
 > launched, but I never see any process running on it, and mptable shows

Hyperthreading is disabled by default in FreeBSD (for
security reasons).  You can enable it via sysctl if
you want (machdep.hyperthreading_allowed=1).

However, note that it might not make your machine any
faster (in fact, a UP kernel might be faster; it depends
on the kind of programs that you're running).  Also
not that there is a potential security issue with hyper-
threading (information leak).

Best regards
   Oliver

-- 
Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M.
Handelsregister: Registergericht Muenchen, HRA 74606,  Geschäftsfuehrung:
secnetix Verwaltungsgesellsch. mbH, Handelsregister: Registergericht Mün-
chen, HRB 125758,  Geschäftsführer: Maik Bachmann, Olaf Erb, Ralf Gebhart

FreeBSD-Dienstleistungen, -Produkte und mehr:  http://www.secnetix.de/bsd

"When your hammer is C++, everything begins to look like a thumb."
        -- Steve Haflich, in comp.lang.c++



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