[mpich-discuss] overlapping reads

[Kokron, Daniel S. (GSFC-610.1)[Computer Sciences Corporation]]

I was wondering if anyone has been able to implement overlapping reads with MPI_File_read_all.

My distributed computational domain has a halo around each sub-domain.  My restart file on disk has only the combined computational domain.  When reading the restart file, I would like each process to the part of the file it 'owns' plus the halo information from neighboring processes.  This means that more than one process will end up reading some parts of the file.  Is this allowed? 

Daniel Kokron
NASA Ames (ARC-TN)
SciCon group
301-286-3959