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Date: Mon, 25 Aug 2003 09:49:07 -0700
From: "David O'Brien" <obrien@freebsd.org>
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Subject: Re: HTT on current
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On Mon, Aug 25, 2003 at 08:27:46AM -0600, Scott Long wrote:
> Since HTT can lead to performance degradation in some (many?) cases,
> the second logical CPU's are halted by default.  They are enabled,
> however, in order for interrupt routing to work right.  Work is ongoing
> to make an HTT-aware scheduler, and make the enabling of the logical
> cores optional.

I've heard this several times and don't doubt it, but it would be nice to
know more about the issue.  What type of cases?  What benchmarks have
been run showing this?