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**Date:** 2024-10-07
ADIOS2 Joined arrays, API simplification, HDF5 subfiling, TOML backend, wildcard file extensions, Performance & Memory
This release adds support for additional I/O features in all backends, and additionally a completely new TOML backend, useful for openPMD-formatted configuration files in scientific workflows.
The ADIOS2 backend now supports joined arrays for simplified storage of particle data in parallel, asynchronous I/O, group tables for enhanced support of ADIOS2 I/O steps, optimized attribute aggregation schemes for large-scale setups and more features.
The HDF5 backend has added support for the "subfiling" virtual file driver intended for I/O performance in large-scale setups, explicit JSON/TOML-based configuration for chunking and independent flushing. The support of exotic datatypes is improved, such as float128 on ARM64/PPC64 and improved support for generically dealing with unknown datatypes.
The JSON backend supports parallel MPI output into separate subfiles, mainly intended for debugging purposes.
The ADIOS1 backend, previously deprecated, has been removed in favor of ADIOS2.
Please consult the upgrade guide for hints on further interacting with old data.
The openPMD-api has been simplified by no longer requiring explicit specification for scalar components via ``RecordComponent::SCALAR`` in its object model.
The addition of wildcard filename extensions (e.g. ``simData.%E`` or ``simData_%T.%E``) simplifies the generic implementation of backend-independent logic, such as post-processing routines.
Rank tables can now be used to pass detailed topology information from writer to reader in staging setups.