add release of 1.15.0-alpha

Author: wkliao

Release/pnetcdf-1.15.0-alpha.tar.gz

@@ -0,0 +1,37 @@
+[PnetCDF](https://parallel-netcdf.github.io) Version 1.15.0-alpha Release Notes (October 27, 2025)
+-------------------------------------
+
+* New feature
+  + Intra-node aggregation for read requests is added. This is the complement
+    of the write requests first implemented in version 1.14.0. Now intra-node
+    aggregation supports both write and read operations. This feature can be
+    enabled by setting hint `nc_num_aggrs_per_node` to the desired number of
+    aggregators per compute node.
+
+* New optimization
+  + A new internal I/O driver, named `pncio`, is added which implements several
+    strategies for performance improvement. A significant portion of this
+    driver was developed to improve performance when Lustre is used. It
+    includes the followings.
+    * When creating a new file, it try to set the Lustre file striping count
+      to the number of compute nodes allocated to the MPI communicator passed
+      to `ncmpi_create()`, when I/O hint `striping_factor` is not explicitly
+      set by the applications.
+    * It automatically sets a good value for hint `cb_nodes` when it is not
+      explicitly set by the applications.
+
+* API deprecated
+  + `vard` APIs introduced in version 1.6.0 are now deprecated. These are the
+    API family that take an argument of MPI derived data type describing the
+    file access layout, which is used as the fileview by the underlying MPI
+    library.
+
+* New error code
+  + `NC_EFSTYPE` indicates an error when an invalid file system type is
+    detected.
+
+* New PnetCDF hint
+  + `nc_pncio` -- To disable or enable the use of the internal `pncio` driver.
+    Its string value is either "enable" or "disable". The default is "enable".
+
+

Release_notes/1.15.0-alpha.md

@@ -32,6 +32,7 @@ <h1>PnetCDF: A Parallel I/O Library for NetCDF File Access</h1>
 
 <h2 id="News">News</h2>
 <ul>
+<li><strong>October 27, 2025</strong>: Alpha Release of PnetCDF 1.15.0 is available.</li>
 <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>Starting from version <a href="https://github.com/Unidata/netcdf-c/blob/v4.4.0/RELEASE_NOTES.md">

index.html

@@ -54,6 +54,13 @@
    <th>Size</th>
    <th>SHA-1 Checksum</th>
  </tr>
+ <tr>
+   <td align=center>October 27, 2025</td>
+   <td align=center><a href=https://github.com/Parallel-NetCDF/Parallel-NetCDF.github.io/blob/master/Release_notes/1.15.0-alpha.md>1.15.0-alpha</a></td>
+   <td><a href="../Release/pnetcdf-1.15.0-alpha.tar.gz">pnetcdf-1.15.0-alpha.tar.gz</a></td>
+   <td>2.6 MB</td>
+   <td>f1391c4b20f9811bcd8af4a510e75bba49477689</td>
+ </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>