[MITgcm-support] Compiling for XT4

[Christopher L. Wolfe]

Hello modelers,

I recently got some time on a Cray XT4 (which is build of AMD  
Opterons) and I'm having a hard time getting good scaling results.  
I'm not really familiar with the architecture, so I cobbled a "build  
option" file from one of the existing AMD option files. Currently,  
I'm using the build options

FC=ftn
CC=cc
LINK=ftn
DEFINES='-DWORDLENGTH=4 -DALLOW_USE_MPI -DALWAYS_USE_MPI -DTARGET_XT4'
CPP='cpp  -traditional -P'
NOOPTFLAGS='-O0'
INCLUDES=-I/opt/xt-mpt/2.0.14/mpich2-64/P/include

FFLAGS='-byteswapio -r8 -Mnodclchk -Mextend'
FOPTIM='-byteswapio -fastsse -O3'

The compiler is Portland Group Fortran. If anyone has any hints for  
additional optimizations and MPI flags, I'd be grateful.

Thanks,
Christopher


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Dr. Christopher L. Wolfe                   858-534-4560
Physical Oceanography Research Division    OAR 357
Scripps Institution of Oceanography, UCSD  clwolfe at ucsd.edu
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