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[Gilles Zerah <gilles.zerah@cea.fr>]

Dear Masayoshi (and all),

Thanks for the lesson you taught us....
One more, if you have some time: do you know exactly the routine(s) 
whose time increase (nonlop is made of many subroutines
like opernl etc..) when you change the optimization option?

Thanks

Gilles


> Dear all,
>
> Sorry for the series of the posts...
> And very sorry to those who take his/her time
> to dwell on this topic; In particular, Marc, I will be pleased
> to owe you a bottle of special Japanese "sake" ... (next time !)
>
> The solution : FCFLAGS_OPT="-O3 -tpp2",
> whiche enables 10-15 times faster than "-O2"(default)
> on Itanium2/ifort. (This is amazing !)
>
> The previous results (the default configuration)
> v.5.2.3:- Total wall clock time (s,m,h):   5824.1      97.07    1.618  
> (-O3 -tpp1)
> v.5.2.4:- Total wall clock time (s,m,h):  12559.0   209.32   3.489 (-O2)
> v.5.3.0:- Total wall clock time (s,m,h)   13056.1    217.60  3.627 (-O2)
> v.5.3.2:- Total wall clock time (s,m,h)   74086.2  1234.77  20.580 (-O2)
> v.5.3.3:- Total wall clock time (s,m,h):  74144.5  1235.74  20.596 (-O2)
> v.5.3.4:- Total wall clock time (s,m,h):  74040.8  1234.01  20.567 (-O2)
>
> Then, the same test with "-O3 -tpp2"
> v.5.2.3:- Total wall clock time (s,m,h):  7652.5   127.54   2.126
> v.5.2.4:- Total wall clock time (s,m,h):  7529.7   125.50   2.092
> v.5.3.0:- Total wall clock time (s,m,h):  7634.1   127.23   2.121
> v.5.3.2:- Total wall clock time (s,m,h):  7662.8   127.71   2.129
> v.5.3.3:- Total wall clock time (s,m,h):  7687.2   128.12   2.135
> v.5.3.4:- Total wall clock time (s,m,h):  7723.7   128.73   2.145
>
> So, the gap between v.5.2.3 and v.5.2.4 (about twice times),
> and the other gap between v.5.3.0 and v.5.3.2 (about 6-7 times)
> can be overcome just with "-O3 -tpp2".
>
> My preoccupation came from the experience with v.4.6.x,
> where I used attached makefile_macros with "-O2" ...
> Oh, yikes !!  Pardon !
> (Still, don't you think this optimization effect is awesome ?
>  So, the binary users might want to compile the source tar.gz
>  with such higher optimization ...)
>
> Thus, I would like to suggest "-O3 -tpp2" as default in configuration
> for Itanium2/ifort... Yann, how do you think ?
>
> BTW, speaking of configuration,
> knowing about "FCFLAGS_FREEFORM"/"FCFLAGS_FIXEDFORM"
> might help for some old computers with old compilers that do not
> understand free/fixed format automatically.
>
> Bien a vous,
> Masayoshi


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