NCMPI

[Rob Latham]

On Tue, Aug 04, 2009 at 04:09:04PM -0500, Dahai Guo wrote:
> for IOR HPC Benchmark,  there is a filesize limitation of 2 GB for
> PnetCDF as follow. Do you know the reason, or just a bug? How can I
> test large file IO in IOR with NCMPI (Certainly I can update the
> code to 1024 )? do I need to set some special environment varibles
> for it? 
> 
>     if ((strcmp(test->api, "NCMPI") == 0) 
>         && ((test->numTasks * test->blockSize * test->segmentCount) 
>             > (2*(IOR_offset_t)GIBIBYTE))) 
>         ERR("file size must be < 2GiB"); 

Hi Dahai.  Sorry for the delay in following up with you: I was away
for the last week.

Galen Arnold asked about this very problem last month.  My solution
remains the same :>

http://lists.mcs.anl.gov/pipermail/parallel-netcdf/2009-July/000856.html

IOR added parallel-netcdf support long ago -- so long ago that we
still called it NCMPI.  Wei-keng has already updated the rest of the
code to use the correct "large file" flag.

==rob

-- 
Rob Latham
Mathematics and Computer Science Division
Argonne National Lab, IL USA