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CESM on NCSA Ember, segfault

S

solsen

New Member
Hi,

Has anyone successfully run CESM on Ember at NCSA?
Ember is an SGI Altix UV. CESM seems to compile and run OK but whenever CAM tries to write a restart file it causes a segfault. Other modules are able to write restart files and CAM can write history files. I'm using intel 11.1.073 and sgi mpt-2.01 with compset B and res f45_g37.

Suggestions welcome,

Seth
 
E

eaton

CSEG and Liaisons
This generally means that you've hit a memory limit. A bit surprising at such a low resolution. Try running with more tasks assigned to the atm. This means customizing the PE layout, as per instructions in the users guide.
 
S

solsen

New Member
It seems that on the SGI Altix UV the mpi library (sgi-mpt) defaults to setting up communication through memory maps as an optimization for the NUMA architecture. This doesn't interact well with CESM. After turning this off with environment variables, e.g., MPI_DEFAULT_SINGLE_COPY_OFF, MPI_MEMMAP_OFF, etc. it seems to be working.
 
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