[MITgcm-devel] going to update build option for pleiades

[Hong Zhang]

Dear all,
Recently pleiades has many upgrades (OS and modules),
so we're going to change the build option accordingly.
some suggested change:
1. use new modules of compiler/mpi/netcdf and change associated INCLUDE/LIB
    (module load comp-intel/2011.2 mpi-sgi/mpt.2.04-fsa netcdf/4.0)
2. FFLAGS: remove -w95 (deprecated soon)
3. FOPTIM:. add -axSSE4.2,SSSE3, add -traceback, remove -xSSE4.2
some justification from Art:
---

for SLES11 OS, users have to use mpt.2.04. The earlier MPT modules won't work
reliably on SLES11;
The module mpi-sgi/mpt.2.04-fsa differs from mpi-sgi/mpt.2.04 in that it
attempts to use "multi-rail" networking to improve message passing throughput;
There are also some optimizer/vectorizer improvements in v12 compilers (comp-intel/2011.2);
-axSSE4.2,SSSE3 instructs
the compiler to build two execution paths in an executable, one for each
architecture. At run time, the executable checks the CPU it's running
on, and then runs the optimized choice. The above produces code optimized for 
both Harpertown and Nehalem/Westmere instruction sets;
Since the use of -traceback produces much more meaningful runtime info
at no cost, I recommend always including the option.
---
We've tested above change and it's OK.
Any comments is welcome before check-in.
hong