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Date: Fri, 27 Jun 2003 18:39:12 -0500
From: Glenn Johnson <gjohnson@srrc.ars.usda.gov>
To: Doug White <dwhite@gumbysoft.com>
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cc: current@freebsd.org
Subject: Re: Hyperthreading
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On Fri, Jun 27, 2003 at 03:46:47PM -0700, Doug White wrote:

> On Fri, 27 Jun 2003, Glenn Johnson wrote:
>
> > I have a P4 processor on order that will support hyperthreading.
> > I was wondering what the general opinion is on enabling HTT for
> > FreeBSD-5 (current).
> >
> > Thanks for any input.
>
> man 4 smp
>
> See the machdep.hlt_logical_cpus sysctl.

Thanks.  I had read the smp manual page.  I know _how_ to enable HTT; I
was wondering whether I _should_ enable it.  It seems the answer is that
it is not beneficial in its current state because the scheduler does not
yet differentiate between physical and logical processors.

-- 
Glenn Johnson
glennpj@charter.net