Peer review of AMD64/FreeBSD article

[Brooks Davis]

On Fri, Mar 12, 2004 at 08:14:59AM -0500, Jem Matzan wrote:
> Hyper-Threading seemed to help with processes that didn't require a 
> heavy CPU load. The OpenSSL tests show it being markedly faster in the 
> smaller algorithms, but lagging way behind the 64-bit Athlon64 when the 
> serious number crunching comes into play. Intel's press kit shows HT 
> (and SSE3) giving an advantage when multitasking with four desktop 
> programs in Windows XP. It's just too hard to show that reliably though. 
> There's a lot of anecdotal evidence to suggest that AMD64 is faster on 
> the desktop (in X) in 64-bit mode than the Prescott is in 32-bit, but 
> I'm having trouble proving it.

I think it would be a mistake to assume the HT is what accounts for
the performance difference.  There are so many other architectural
differences it's hard to see how you could isolate the effects of
HT.  My suspicition is that better performance on small 
algorithms is due to them being more or less memory bound (and thus
similar to the pure synthetic benchmarks).

-- Brooks

-- 
Any statement of the form "X is the one, true Y" is FALSE.
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