collective memory-mapped array

[Jose Gracia]

Dear all,

I am having problems writting a 4-dimensional (actually, the first dim 
has length one only) memory-mapped array to disk collectively. The array 
is not strided but mapped non-trivially in memory. The call I want and 
doesn't work (ie code hangs forever) is:


status=ncmpi_put_varm_double_all(ncid,varidp[6],start4,count4,stride4,imap4,tem_bck+offset);


The strange thing is, that writing in independent mode works and 
produces the expected result:

status=ncmpi_begin_indep_data(ncid);
status=ncmpi_put_varm_double(ncid,varidp[6],start4,count4,stride4,imap4,tem_bck+offset);
status=ncmpi_end_indep_data(ncid);



I am trying this with PNetCDF 1.0.3 and older versions (1.1.0 will not 
compile for me) compiled with Intel compiler V11.0 and Open MPI V1.3. on 
a lustre filesystem (though tests on NFS mounted FS didn't work either).

I would love to provide a minimal example showing the error, but I can't 
as all my test codes work fine :(

The strange thing is, that running the same code on a big (as in lots of 
memory) single-node machine with the same number of MPI tasks works 
fine. But this isn't an option for production runs.

I would appreciate any hints on what might be going on.


Cheers,
Jose

-- 

Dr. Jose Gracia		email:  gracia at hlrs.de
HLRS, Uni Stuttgart	http://www.hlrs.de/people/gracia
Nobelstrasse 19		phone: +49 711 685 87208
70569 Stuttgart		fax:   +49 711 685 65832
Germany