Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Parallel netCDF I/O #187

jhamman opened this issue Jan 10, 2015 · 0 comments

Parallel netCDF I/O #187

jhamman opened this issue Jan 10, 2015 · 0 comments


Copy link

jhamman commented Jan 10, 2015

I found my notes on the comment/question I was going to ask a few weeks back on #23. I'm going to put them here so I don't loose them again and we can close the issue if we decide not to use parallel netCDF I/O.

Parallel access to netCDF file routines are available from two sources:


netCDF4 is is supported in C, C++, Fortran, Python, Java, etc. Parallel I/O support is likely limited to the C and Fortran languages.

Summary from netCDF4 Parallel I/O documentation:

NetCDF-4 provides access to HDF5 parallel I/O features for netCDF-4/HDF5 files.

NetCDF classic and 64-bit offset format may not be opened or created for use with parallel I/O. (They may be opened and created, but parallel I/O is not available.)

A few functions have been added to the netCDF C API to handle parallel I/O.


Parallel netCDF (PnetCDF) is supported in C, Fortran 77, Fortran 90, and C++.

A summary from the PnetCDF Github page:

Parallel netCDF (PnetCDF) is a library providing high-performance parallel I/O
while still maintaining file-format compatibility with Unidata's NetCDF,
specifically the CDF and CDF-2 formats. Although NetCDF supports parallel I/O
starting from version 4, the files must be in HDF5 format. PnetCDF is currently
the only choice for carrying out parallel I/O on files that are in classic
formats (CDF-1 and 2).

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
None yet

No branches or pull requests

2 participants