• November 2, 2018: The official PnetCDF project web pages have migrated to github.com from its previous location at https://trac.mcs.anl.gov/projects/parallel-netcdf.
• July 2, 2018: Release of PnetCDF version 1.10.0 contains a new feature of using locally or globally accessible burst buffers.
• June 23, 2018: PnetCDF source code repository has moved from its SVN server at Argonne National Laboratory to https://parallel-netcdf.github.io.

1.9.0

• December 19, 2017: PnetCDF 1.9.0 is released. See 1.9.0 Release Note.
• November 1, 2017: PnetCDF 1.9.0.pre1 is available as a pre-release of version 1.9.0.

1.8.1

• January 28, 2017: PnetCDF 1.8.1 is released (the latest stable version). See 1.8.1 Release Note.

1.8.0

• December 19, 2016: PnetCDF 1.8.0 is released (the latest stable version). See ReleaseNotes-1.8.0.
• November 15, 2016: a preview release of PnetCDF 1.8.0 is available.
• March 3, 2016: PnetCDF 1.7.0 is released (the latest stable version). See ReleaseNotes-1.7.0.
• We continue working with the netCDF team at Unidata to improve CDF-5 and PnetCDF features in netCDF-4.

1.7.0pre1

• January 12, 2016: PnetCDF 1.7.0pre1 is available as a pre-release of version 1.7.0. See release note.
• We work with the netCDF team at Unidata to integrate CDF-5 and PnetCDF features in netCDF-4. See ​release note of 4.4.0 candidate RC4 for more information.

1.6.1

• June 1, 2015: PnetCDF 1.6.1 is released (the latest stable version). See ReleaseNotes-1.6.1.
• We are developing a ​patch to teach netCDF-4 to access CDF-5 files both in sequential and parallel. We encourage netCDF-4 users to give it a try and welcome all comments.

1.6.0

• February 2, 2015: PnetCDF 1.6.0 is released. See ReleaseNotes-1.6.0.

1.6.0.pre1

• January 3, 2015: a test release of PnetCDF 1.6.0.pre1 is available. See ReleaseNotes-1.6.0.pre1 for more details.

1.5.0

• July 8, 2014: PnetCDF 1.5.0 is released. See ReleaseNotes-1.5.0.
• C++ APIs are now available in 1.5.0.

1.5.0.pre1

• May 16, 2014: a test release of PnetCDF 1.5.0.pre1 is available. See ReleaseNotes-1.5.0.pre1 for more details.

1.4.1

• December 23, 2013: PnetCDF 1.4.1 is released. See ReleaseNotes-1.4.1 for more details.
• Fortran header file, pnetcdf.inc, now can be included in both fixed and free-formed Fortran programs.
• Initial ​subfiling feature has been added to 1.4.1.

1.4.0

• November 17, 2013: PnetCDF 1.4.0 is released. See ReleaseNotes-1.4.0 for more details.
• Fortran 90 APIs are now available in 1.4.0.
• New APIs, ncmpi_get/put_varn_<type> for reading/writing a list of sub-requests to a single variable. Available for F77 and F90 as well.
• FLASH-IO benchmark using PnetCDF is now part of the source code release.

1.4.0.pre1

• September 19 2013: PnetCDF 1.4.0.pre1 test release. See ReleaseNotes-1.4.0.pre1 for more details.

1.3.1

• September 24, 2012: PnetCDF 1.3.1 released. See ReleaseNotes-1.3.1 for more details.

1.3.0

• 26 June 2012: PnetCDF 1.3.0 released. See ReleaseNotes-1.3.0 for more details.
• In the 1.3.0 release, the unsigned and 64-bit integer data types are supported for CDF-5 format. The unsigned data types include NC_UBYTE, NC_USHORT, NC_UINT, and NC_UINT64. The 64-bit integer data types are NC_INT64 and NC_UINT64.
• New APIs for supporting more data types are added. For C, they are ncmpi_(i)put/(i)get_var*_ushort/uint/longlong/ulonglong. For Fortran, they are nfmpi_(i)put/(i)get_var*_int8.
• A new set of "buffered"-put APIs is supported in 1.3.0 release. The nonblocking iput/iget APIs require the contents of user buffers not to be changed until the wait call completed. The bput APIs use a user attached buffer to make a copy of request data, so the user buffer is free to change once the bput call returns.
• The special character set, "special2", and multi-byte UTF-8 encoded characters introduced in the CDF-2 file format for variable, dimension, and attribute name strings are now supported.
• A set of example programs and QuickTutorial are now available.
  

1.2.0

• 19 August 2010: PnetCDF 1.2.0 released. See ReleaseNotes-1.2.0 for more details.
• Nonblocking I/O is redesigned in the 1.2.0 release. It defers the I/O requests until "wait" call, so small requests can be aggregated into large ones for better performance.
• Two new hints, nc_header_align_size and nc_var_align_size, are added. The former allows pre-allocation of a larger header size to accommodate new header data in case new variables or attributed are added later. The latter aligns the starting file offsets of non-record variables. Refer to VariableAlignment for a more detailed description.
• Data consistency control has been revised. A more strict consistency can be enforced by using NC_SHARE mode at the file open/create time. In this mode, the file header is synchronized to the file if its contents have changed. Such file synchronization of calling MPI_File_sync() happens in many places, including ncmpi_enddef(), ncmpi_redef(), all APIs that change global or variable attributes, dimensions, and number of records.
• As calling MPI_File_sync() is very expensive on many file systems, users can choose more relaxed data consistency, i.e. by not using NC_SHARE. In this case, file header is synchronized among all processes in memories. No MPI_File_sync() will be called if header contents have changed. MPI_File_sync() will only be called when switching data mode, i.e ncmpi_begin_indep_data() and ncmpi_end_indep_data().