Collective Metadata API

Not sure if we are aware of this in HDF5:
https://www.hdfgroup.org/HDF5/docNewFeatures/NewFeaturesCollectiveMetadataIoDocs.html

Advertised as

> Parallel Library
> -----------------
> - Collective Metadata I/O
>
> Calls for HDF5 metadata can result in many small reads and writes.
> On metadata reads, collective metadata I/O can improve performance
> by allowing the library to perform optimizations when reading the
> metadata by having one rank read the data and broadcasting it to
> all other ranks.
>
> Collective metadata I/O improves metadata write performance through
> the construction of an MPI derived datatype that is then written
> collectively in a single call. For more information, see
> https://www.hdfgroup.org/HDF5/docNewFeatures/NewFeaturesCollectiveMetadataIoDocs.html.

In [HDF5 1.10](https://support.hdfgroup.org/ftp/HDF5/current/src/unpacked/release_docs/HISTORY-1_10.txt)?