Differences between AMD and Intel CPUs [was: Re: Dragonfly and Hyperthreading....]

[David Xu]

EM1897 at xxxxxxx wrote:

If you paid that much for an SMP system running FreeBSD,
then you're flying blind for certain. You've overpaid 
because you don't know enough about hardware to know
what you're doing. Your xeon systems "sound like jets"
because you've bought something that sounds like a jet.
A P4 system with a single blower (which is what we use)
will likely outperform what you've bought for 1/5th the
cost. (my current 5.3R benchmarks show that FreeBSD
with 2 3.06Ghz xeons is actually slower than a single
P4 processor system. They've done a helleva job!).

I wonder what benchmark you are running ? if you are
testing against libpthread, that might be the trouble.
I don't have a machine installed  5.3R, but with FreeBSD-CURRENT,
and libthread, the SMP performance is really increased, for example,
I have a test program from a book, the program recursivly searchs
a word concurrently in a directory by forking multiple threads,
on UP, it takes 11 seconds to complete, on SMP, it takes 7 seconds,
note that the machine is aged PIII SMP box, with a poor VIA 694T
chipset (can do SMP, but not performance wise).
David Xu