nfmpi_iput_vara_double + nfmpi_wait_all

[Wei-keng Liao]

Hi, Max,

Combining multiple noncontiguous requests should work for the nonblocking I/O.
I hope the "noncontiguous" you are referring is the same as what I understand.
In order to ensure that, could you please send us a copy of your test codes?

Wei-keng

On Aug 24, 2010, at 1:05 PM, Maxwell Kelley wrote:

> 
> Hello,
> 
> (As this is my first post: many thanks to the developers!)
> 
> I've been trying the nonblocking I/O interface described at
> 
> http://trac.mcs.anl.gov/projects/parallel-netcdf/wiki/CombiningOperations
> 
> to combine writes of domain-decomposed arrays via calls to nfmpi_iput_vara_double() followed by an nfmpi_wait_all().
> 
> When a combination of write requests corresponds to a contiguous set of arrays in the output file (sequential netcdf IDs), the results are always correct.  However, combining write requests for a noncontiguous set of arrays sometimes produces incorrect results.  Is this latter access pattern permitted, and has it been extensively tested?  I may be doing something wrong which happens to be non-fatal only for contiguous collections of arrays.
> 
> I realize that batched-up writes for noncontiguous subsets of a file may not make sense from a performance standpoint.
> 
> Thanks for any help,
> 
> -Max
> 
> -------------------------------------------------------------------
> Maxwell Kelley
> Center for Climate Systems Research, Columbia Univ. Earth Institute
> @
> NASA Goddard Institute for Space Studies
> 2880 Broadway                                  kelley at giss.nasa.gov
> New York NY 10025                                 1-212-678-5669
> -------------------------------------------------------------------
>