Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 22 May 2002 10:27:59 -0700
From:      Alfred Perlstein <>
To:        "Dorr H. Clark" <>
Cc:        freebsd-smp@FreeBSD.ORG
Subject:   Re: hyperthreading: myth or legend? (was Re: hyperthreading? (was Re: question))
Message-ID:  <>
In-Reply-To: <>
References:  <> <>

next in thread | previous in thread | raw e-mail | index | archive | help
* Dorr H. Clark <> [020522 09:58] wrote:
> I don't have access to a fancy Xeon, I just have 
> a PIII dual-banger, so I'm relying on the list traffic.  
> To summarize the past two months:
> On Thu, 14 Mar 2002, John Baldwin wrote:
> On  Thu, 14 Mar 2002, Terry Lambert wrote:
> On Tue, 23 Apr 2002, FiberOps wrote:
> On Tue, 23 Apr 2002, John Baldwin wrote:
> On 23-Apr-2002 FiberOps wrote:
> This final message was not followed up except by me,
> although someone else informed me that while the CPUs
> launch, FreeBSD can't run processes on them.
> So I thought I'd try to stir up an answer to the original question:
> For the latest Xeon motherboards, does FreeBSD 4.x stable
> support hyperthreading?  If not, does the current TOT?  
> If not, why not?  Is gcc an issue or not?  If gcc is an issue,
> would this be an obstacle for all gcc-based OSes, 
> not just FreeBSD, most prominently among these Linux?
> Clear answers gratefully appreciated,

I'm glad you chose to take the word of a couple of people
that have never used a hyperthreading board above what I've
already told you.

Here's what I know:
The additional CPUs probe.

A benchmarking utility reports equivelant performance to a 4 way

-Alfred Perlstein []
'Instead of asking why a piece of software is using "1970s technology,"
 start asking why software is ignoring 30 years of accumulated wisdom.'
Tax deductible donations for FreeBSD:

To Unsubscribe: send mail to
with "unsubscribe freebsd-smp" in the body of the message

Want to link to this message? Use this URL: <>