Nicolas Calimet wrote:
>> The test with povray compiled without optimisations on my pc has just 
>> ended :  45 minutes  13.0 seconds (2713 seconds)
>>
>> 3 seconds longer : this is not signifiant.
> 
> 
>     So if I understand you correctly, you do obtain:
> 
> gcc 3.2.2 -march=i586     : 45 minutes 13 seconds ( 2713 seconds )
> gcc 3.2.2 -march=pentium4 : 36 minutes 43 seconds ( 2203 seconds )
> icc 8.0   -tpp7           : 33 minutes 01 seconds ( 1981 seconds )
> 
>     Is this right ?
> 
>     I'd be interested if you could post the full gcc/icc command-line
> that you actually used to compile the binaries  :-)
> 
>     - NC
> 


The GCC CFLAGS variable was the one used in the original one with only 
'i586' replaced by 'pentium4'
  the icc CFLAGS variable was :
CFLAGS = -O3 -mcpu=pentium4 -march=pentium4 -ip
(-tpp7 is like -mcpu=pentium4, -march=pentium4 could be replaced by -xP)
-ip adds Interprocedural Optimizations (IPO)

more optimisations could be realized with Profile-guided Optimizations 
(PGO) and static linking

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