Hi,
On Thu, 22 Jan 2004, 10:14am +1100, [log in to unmask] wrote:
> For our codes (numerical weather and climate models) the Intel
> compiler's P4 specific optimizations have a large benefit.
>
> Time per simulated day on Intel P4 processor
>
> Options Time (s)
> ifc -O2 319 Intel compiler
> ifc -O2 -tpp6 -xK 299 P3 specific options
> ifc -O2 -tpp7 -xW 213 P4 specific options
(P3-P4)/P3 = 29% => impressive.
> Another model
>
> ifc -O2 667
> ifc -O2 -tpp6 -xK 504
> ifc -O2 -tpp7 -xW 452
(P3-P4)/P3 = 10% => uninteresting.
Do you have a sense for what makes the first model so much
more susceptible to performance tuning?
-P.
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