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Re: P4 optimized Debian GNU/Linux?

On Fri, 2004-02-27 at 08:40, Adam Majer wrote:
> Turbo Fredriksson wrote:

> >His word was "it WAY faster!". No numbers, just those three words. Got'a
> >mean something...

> Ok, I have actually done a little test program. The problem is that 
> optimizing an application with gcc 3.3 might actually make things 
> *slower*. I have a P4 (2.6GHz) and an K7 2000+ workstation. When I run a 
> simple program that only does,


> PS. I know for a fact that optimizing things with SSE or SSE2 *slows 
> down* the program if compiled with gcc. This happed for both Athlon and 
> P4 when I tried to optimize a loop-heavy magic square program.

FWIW, the P4 is extremely bad with unrolled loops in my experience, to
the point where a CPU intensive application we run here goes faster on a
P3 1GHz than it does on a P4 1.7GHz, when running i386 optimised code.

In summary, we run this application tens of thousands of times every
night, and get consistent results.

Miah Gregory

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