Omar Sobh and Claude Sonnet 4.6
d6c4d4f111
feat: implement filter codecs, format write extensions, and MPI-IO VOL
...
All three SDD plans fully wired and committed to main:
Filter Codecs (FC):
- FC-1: Implement float E-scale in scaleoffset_decompress (value = minval +
code * 2^E, negative exponents via cast to i32); add two round-trip tests.
- FC-2: filters_szip.rs — feature-gated SZIP decode via libaec FFI; SZIP
dispatch arm added to decompress_chunk.
- FC-3: libaec-sys workspace crate with pkg-config probe and aec_buffer_decode
FFI binding; added to workspace members.
Format Write Extensions (FWE):
- FWE-1: GroupBuilder::add_external_link() API; wired through FinishedGroup
→ GrpFlat → file_writer pass 1/2/3 (OH size, layout cursor, final write);
external_link_write_roundtrip test.
- FWE-2: data_layout_write.rs — serialize_vds_mappings with length_size param
and version 0/1 (external vs same-file) selection; declared as pub mod.
- FWE-3: with_virtual_sources empty-mapping guard (Important #9 ) — empty vec
is silently ignored; vds_empty_mapping_list test updated to assert non-VDS
layout results.
MPI-IO VOL Backend (MPI):
- MPI-1/2/3: mpi_vol.rs — MpiVol implementing VirtualObjectLayer; root-read
+ broadcast collective read; gather + root-write collective write; feature-
gated mpi-io feature; wired into clawhdf5-io lib.rs.
- MPI-4: mpi_io_bench binary (h5bench-equivalent MPI-IO throughput bench).
mpi_vol.rs reviewer fixes:
- Doc-comment updated to accurately describe root-read+broadcast pattern
(not MPI_File_read_at); MpiVol::expected_capabilities() associated fn
added so tests can verify capabilities without a live MPI universe;
rank_and_size_stub_values renamed to no_feature_error_contains_feature_name.
Workspace check: zero warnings, 20 test suites pass.
Co-Authored-By: Claude Sonnet 4.6 <[email protected]
2026-06-30 11:41:41 +00:00
