release of PnetCDF 1.14.1

Author: wkliao

Release/pnetcdf-1.14.1.tar.gz

@@ -0,0 +1,101 @@
+[PnetCDF](https://parallel-netcdf.github.io) Version 1.14.1 Release Notes (July 31, 2025)
+------------------------------------------------------------------------------
+
+* New optimization
+  + When file header extent size grows, moving the data section to a higher
+    file offset has changed to be done in chunks of 16 MB per process.
+    See [PR #174](https://github.com/Parallel-NetCDF/PnetCDF/pull/174),
+
+* Configure options
+  + For PnetCDF developers, the requirement for libtool version has been
+    changed to 2.5.4, due to an issue on Mac OS when using OpenMPI. See
+    [Issue #155](https://github.com/Parallel-NetCDF/PnetCDF/issues/155),
+    [Issue #163](https://github.com/Parallel-NetCDF/PnetCDF/issues/163),
+    and [PR #164](https://github.com/Parallel-NetCDF/PnetCDF/pull/164).
+
+* New APIs
+  + A set of APIs that read the header of a CDL file header and allow users to
+    query the metadata defined in the CDL file. These APIs can be useful for
+    creating a program (such as an I/O benchmark) based on an output netCDF
+    file from another application (a CDL file can be generated by running the
+    utility `ncmpidump/ncdump`). See
+    [PR #177](https://github.com/Parallel-NetCDF/PnetCDF/pull/177).
+    * `cdl_hdr_open()` opens and parses the CDL file's header
+    * `cdl_hdr_inq_format()` returns file format version
+    * `cdl_hdr_inq_ndims()` returns number of dimensions defined in CDL file
+    * `cdl_hdr_inq_dim()` returns metadata of a dimension
+    * `cdl_hdr_inq_nvars()` returns number of variables
+    * `cdl_hdr_inq_var()` returns metadata of a variable defined in CDL file
+    * `cdl_hdr_inq_nattrs()` returns number of attributes of a given variable
+    * `cdl_hdr_inq_attr()` returns metadata of an attribute
+    * `cdl_hdr_close()` closes the CDL file
+  + The CDL Header C Reference Manual is available in
+    [cdl_api_guide.md](doc/cdl_api_guide.md). See
+    [PR #184](https://github.com/Parallel-NetCDF/PnetCDF/pull/184).
+
+* Bug fixes
+  + Fix setting of user hint nc_ibuf_size.
+    See [PR #161](https://github.com/Parallel-NetCDF/PnetCDF/pull/161).
+
+* New example programs
+  + examples/C/create_from_cdl.c shows how to call the new CDL header APIs to
+    create a netCDF file with the same metadata.
+
+* New programs for I/O benchmarks
+  + WRF-IO contains an extraction of the I/O kernel of WRF (Weather Research
+    and Forecast Model, a weather prediction computer simulation program
+    developed at NCAR) that can be used to evaluate the file I/O performance
+    of WRF. It's data partitioning pattern is a 2D block-block checkerboard
+    pattern, along the longitude and latitude.
+    See [PR #165](https://github.com/Parallel-NetCDF/PnetCDF/pull/165)
+    and [PR #181](https://github.com/Parallel-NetCDF/PnetCDF/pull/181).
+
+* New test program
+  + test/cdf/tst_cdl_hdr_parser.c tests the new CDL header APIs.
+  + test/testcases/tst_grow_header.c tests header extent growth by re-entering
+    the define mode multiple times and add more fix-sized and record variables.
+
+* Clarifications about of PnetCDF hints
+  + There are three ways in PnetCDF for user to set hints to align the starting
+    file offset for the data section (header extent) and record variable
+    section.
+    1. through a call to API `nc_header_align_size` by setting arguments of
+       `h_minfree`, `v_align`, `v_minfree`, and `r_align`.
+    2. through an MPI info object passed to calls of `ncmpi_create()` and
+       `ncmpi_open()`. Hints are `nc_header_align_size`, `nc_var_align_size`,
+       and `nc_record_align_size`.
+    3. through a run-time environment variable `PNETCDF_HINTS`. Hints are
+       `nc_header_align_size`, `nc_var_align_size`, and `nc_record_align_size`.
+  + As the same hints may be set by one or more of the above methods, PnetCDF
+    implements the following hint precedence.
+    * `PNETCDF_HINTS` > `ncmpi__enddef()` > `MPI info`.
+    * 1st priority: hints set in the environment variable `PNETCDF_HINTS`, e.g.
+      `PNETCDF_HINTS="nc_var_align_size=1048576"`. Making this the first
+      priority is because it allows to run the same application executable
+      without source code modification using different alignment settings
+      through a run-time environment variable.
+    * 2nd priority: hints set in the MPI info object passed to calls of
+      `ncmpi_create()` and `ncmpi_open()`, e.g.
+      `MPI_Info_set("nc_var_align_size", "1048576");`. The reasoning is when a
+      3rd-party library built on top of PnetCDF implements its codes using
+      'ncmpi__enddef'. An application that uses such 3rd-party library can pass
+      an MPI info object to it, which further passes the info to PnetCDF. This
+      precedence allows that application to exercise different hints without
+      changing the 3rd-party library's source codes.
+    * 3rd priority: hints used in the arguments of `ncmpi__enddef()`, e.g.
+      `ncmpi__enddef(..., v_align=1048576,...)`.
+  + PnetCDF I/O hint `nc_header_align_size` is essentially the same as hint
+    `nc_var_align_size`, but its name appears to be closer to the hint's
+    intent, i.e. to reserve some space for the header growth in the future when
+    new data objects are added. Please note when both hints are set, only hint
+    `nc_var_align_size` will take effect and `nc_header_align_size` ignored.
+  + When there is no fix-sized variable (i.e. non-record variable) defined,
+    argument `v_minfree` passed to `ncmpi__enddef()` is ignored. In this
+    case, users should set `h_minfree`, if an extra header space is desired.
+  + When there is no fix-sized variables defined and none of hints
+    `nc_header_align_size`, `nc_var_align_size`, or argument `v_align` is set,
+    `nc_record_align_size` or `r_align`, if set, will be used to align the
+    header extent.
+  + For the above update to the hint precedence, see
+    PnetCDF See [PR #173](https://github.com/Parallel-NetCDF/PnetCDF/pull/173).
+

Release_notes/1.14.1.md

@@ -32,8 +32,8 @@ <h1>PnetCDF: A Parallel I/O Library for NetCDF File Access</h1>
 
 <h2 id="News">News</h2>
 <ul>
+<li><strong>July 31, 2025</strong>: Release of PnetCDF 1.14.1 is available.</li>
 <li><strong>November 12, 2024</strong>: <a href=https://github.com/Parallel-NetCDF/PnetCDF-Python>PnetCDF-Python</a> package 1.0.0 is released.</li>
-<li><strong>November 11, 2024</strong>: Release of PnetCDF 1.14.0 is available.</li>
 <li>Starting from version <a href="https://github.com/Unidata/netcdf-c/blob/v4.4.0/RELEASE_NOTES.md">
 4.4.0</a>, the NetCDF library developed at Unidata supports the CDF-5 file
 format for both sequential and parallel file access.</li>

index.html

@@ -54,6 +54,13 @@
    <th>Size</th>
    <th>SHA-1 Checksum</th>
  </tr>
+ <tr>
+   <td align=center>July 31, 2025</td>
+   <td align=center><a href=https://github.com/Parallel-NetCDF/Parallel-NetCDF.github.io/blob/master/Release_notes/1.14.1.md>1.14.1</a></td>
+   <td><a href="../Release/pnetcdf-1.14.1.tar.gz" onClick="var that=this; ga('send', 'event', 'PnetCDF', 'Source Download (GZ)', 'pnetcdf-1.14.1.tar.gz', 1); ga('pnetcdfTracker.send', 'event', 'PnetCDF', 'Source Download (GZ)', 'pnetcdf-1.14.1.tar.gz', 1); ga('parallelnetcdfTracker.send', 'event', 'PnetCDF', 'Source Download (GZ)', 'pnetcdf-1.14.1.tar.gz', 1); setTimeout(function(){location.href=that.href;},500); return false;">pnetcdf-1.14.1.tar.gz</a></td>
+   <td>2.4 MB</td>
+   <td>ed59e4323d7ea7263d0ee057350b86ede900ec1d</td>
+ </tr>
  <tr>
    <td align=center>November 11, 2024</td>
    <td align=center><a href=https://github.com/Parallel-NetCDF/Parallel-NetCDF.github.io/blob/master/Release_notes/1.14.0.md>1.14.0</a></td>