An "Open issues" table at the top links each open entry; fixed entries
move to "Fixed (history)", newest first, keeping the date, PR, affected
releases and what users must do. Open entries re-checked against main
(9b5803f): the remaining audit gaps are gathered into one entry, the
range-read and remote limits no longer contradict themselves (Python and
the browser open URLs; SWMR reading is File::open_swmr), and the
nondeterministic damaged-chunk error, fixed in PR #19, has its own
history entry.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
CHANGELOG (Unreleased): the v1 B-tree lookup, `Storage::hint`, the walks
that go on past a missing node, and the counts before and after on an
h5py file like the reviewer's (3000 datasets, 198 MB, earliest and
latest libver, 1 MiB and 64 KiB blocks), the corpus read lazily at
512 B and 64 KiB blocks, and the Node/Chromium suite.
known-issues (browser limits, round trips): the new counts, why the
passes cannot go lower (the chain of addresses), why merging nearby
requests does not help such a file, and that a second listing refetches
at 1 MiB blocks when the file's metadata blocks exceed `cacheSize`.
range-reads.md M4 status and the viewer README follow.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
The last 3 our-errors and 2 mismatches were documented as not ours but
still counted against us, on a heuristic (any big-endian VL mismatch) and
a fixed list.
- ref.py checks that the installed h5py returns big-endian VL elements
with the file's bytes under a little-endian dtype (writing and reading
a vlen('>f4') in memory) and, if so, relabels them with the file's byte
order before hashing, marking the object `ref_fix`. The values are now
compared: attr_datatypes.hdf5 /@vlen_uint64 and tcomplex_be.h5
/VariableLengthDatasetFloatComplex are identical to ours (h5dump 1.14.6
prints the same (1, 2), (3, 4, 5), (42)).
- ref_bugs.py re-reads each object h5py reads only through a libhdf5 bug
in six processes with different heaps (import order, MALLOC_PERTURB_).
Values the file determines are the same every time; these three change
(6, 6 and 3 distinct results), so they are over-read memory, not data
clawhdf5 could match. compare.py classifies a file `ref-bug` only when
every difference is such an object confirmed in the same run.
- report.py: the ref-bug class, the evidence table, the corrected
objects; test_ref.py covers both (run in the nightly job).
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
The first run of the day could not get an idle tank: two orphaned h5py
SWMR reader processes from earlier interop tests (since stopped) kept a
core each busy. Re-run with the load below 2 at every round:
ObjectHeader::parse is +4.2% (real: the ranges do not overlap; about 2.5
ns per header, not visible in the facade listing, which is -1.7%); full
deflate reads +1.7% (1 thread) to +36% (16 threads); the -5.6% single-
thread contiguous hyperslab result from the loaded run is noise (-1.7%,
overlapping ranges) and is withdrawn from known-issues.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
8f59b2e (main before PR #18) against 7a8fae0, separate binaries,
alternating rounds on tank (6 Criterion rounds of local_metadata_bench,
3 of concurrent_read --decode-threads 1). Still provisional: two orphaned
h5py test processes held the load at 2.1-2.6 and the load < 2 gate was
not met in 2 hours.
The facade listing regression is gone (-0.8%). ObjectHeader::parse x401
is +4.1% and one-thread contiguous hyperslab reads -5.6%; both listed as
open in known-issues. Full deflate reads are 7-23% faster.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
CHANGELOG (M4 section), known-issues (wasm limits: maxFetch, the 1 GiB
decode limit, the 4 GiB file limit on wasm32, bodies cut off at their
length, listing passes, the cross-origin tests, and a pre-existing
nondeterministic error choice on cve-2025-2310.h5 that can fail the
native corpus comparison), the viewer README (options, how listing
costs, tests) and the M4 status in docs/design/range-reads.md.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
h5py supports boolean masks for reads and writes; clawhdf5 supports
neither, so a mask is an unsupported operation (NotImplementedError, as
for every other edit the bindings cannot do), not an invalid key.
Tests: test_unsupported_edits_are_clear_errors (1-D, N-D and per-axis
mask writes, file unchanged) and test_boolean_masks_are_refused (reads).
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
FileEditor re-opened its path to plan each edit but wrote through the file
it held open, and the Python 'r+' handle re-opened the path after every
edit to read. When the path came to name another file between edits (a
rename or replacement, or a relative path after os.chdir), an edit was laid
out from the other file's metadata and written into the held one,
corrupting it, and later reads came from the other file (the review's
repro: h5py then reports "invalid dataset size, likely file corruption").
The editor now plans from a mapping of its own file (a clone of the held
descriptor, dropped before the edit writes) and canonicalises its path at
open. New FileEditor::reader() opens the held file anew for reading,
without sharing the editor's flock (a mapping of a cloned descriptor holds
the lock until unmapped): through /proc/self/fd on Linux, which follows a
renamed file; elsewhere by path, refused on Unix when the path no longer
names the held file. The Python handle reads through it and keeps no path;
a 'w' file is written at the absolute path it was opened with.
Tests: edit_tests.rs edits_go_to_the_file_held_not_the_path; test_edit.py
test_relative_path_and_chdir and test_path_replaced_between_edits.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
FileEditor::resize (on main since PR #18, a4c2ace) scrambled the values of
a chunked dataset whose dataspace records no maximum dimensions when it
shrank it: clawhdf5's writer stores such a dataspace for every chunked
dataset created without a maxshape, the maximum is then the current
dimensions, and the Fixed Array index linearises chunks by the maximum, so
patching only the current dimensions moved every chunk after the first
row. h5py, h5dump and our reader all read the wrong values; the dataset
could not grow back either.
libhdf5 never writes such a dataspace (H5S_set_extent_simple records the
maximum, equal to the dimensions when none is given); reading one,
H5S_extent_get_dims reports the current dimensions as the maximum and
H5S_set_extent checks against none, so its own H5Dset_extent scrambles
such a file the same way. The editor now records the maximum libhdf5 would
have written (the dimensions the index was built with) before changing the
current ones, moving the grown dataspace message in the header when it
must. The writer records the maximum of every chunked dataset too, so
h5py can resize what clawhdf5 writes (the pinned file hashes of three
no-maxshape cases in plugin_filters_interop change by 8 bytes a dimension).
Tests: edit_resize_interop.rs (a 2.7.0-written fixture, new FileBuilder
files and h5py files through shrinks, zero extents and growth, against a
model with our reader and h5py; h5py resizing a FileBuilder file), and in
test_edit.py resizes checked against a numpy model, independently of h5py.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
read_string, read_string_bytes, read_string_selection, read_vlen and
read_vlen_selection now retry as a whole, the global-heap decoding after the
read included; so do File::decode_strings / decode_string_bytes /
decode_vlen, Group::datasets / groups / attrs / attr, Dataset::attrs / attr,
the typed full reads (read_f64 ...), the header messages behind shape() and
dtype() (a shared message is read from another header), and
verify_provenance. Before, a transient failure on those reached the caller.
Attribute reads leave out an attribute they cannot read (or return a
variable-length string one as AttrValue::Raw) instead of failing, which hid
a transient error as a missing or raw attribute: on a live file such an
error of a retried kind now runs the read again too, and after the last
attempt the last result is returned as before. The format crate gains
find_attribute_reporting_in, which returns the errors find_attribute_in
skips (dense name-index lookups dropped them). The zero-copy reads need the
file in memory, which a live file never is, so they have nothing to retry.
Test: a storage that fails one read with a checksum mismatch; for 14 read
paths over a new fixture (tests/fixtures/swmr_strings_attrs.h5, an h5py
copy with the SWMR-write flag: vlen strings, vlen int32, dense attributes),
each read the path makes fails once in turn and the path must return the
same result with exactly one retry. It fails on the previous commit
(root.attrs, read 0). Dataset::attr on dense attributes returned None
before find_attribute_reporting_in.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
The README example looped while swmr_writer_active(), which never ends when
the writer crashed or was killed: libhdf5 clears the SWMR-write flag only on
close (the mid-write fixture keeps it set for good). The loop now also stops
after a minute without growth, and the README, the swmr_writer_active docs
(with the same loop as a compiled no_run doctest) and the design say why.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
is_transient_format counted every format error but a handful as transient,
so on an open_swmr handle a permanent failure (a file that is not HDF5, an
unsupported version or message, a truncated file) was retried 100 times,
about 0.9 s of pauses per failing operation. Now only these are retried:
a checksum mismatch; a read past the file's current end (UnexpectedEof;
libhdf5 reads zeros there, which fail the checksum); and an object header
prefix whose signature or version does not decode, which libhdf5's
H5C__load_entry also retries (a header garbled whole fails there before its
checksum). Everything else is returned at once.
Tests: a unit test that every permanent kind returns after one call within
50 ms and every transient kind is retried to the limit; open_storage_swmr
of a non-HDF5 buffer returns SignatureNotFound within 100 ms (0.87 s before)
and a missing name on a live file fails without retries. The torn-read and
live h5py-writer tests still pass.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
A file opened with open_swmr whose superblock does not have the SWMR-write
flag (its writer has closed it) is now read exactly as File::open reads it:
bounded by its recorded end of file, through the chunk cache, each
operation tried once, and is_swmr_read() is false. Before, every file opened
with open_swmr ignored its recorded end of file, so a closed file whose end
of file is below its length (h5clear_fsm_persist_less.h5, or the mid-write
fixture with its flags cleared) listed and read objects that File::open and
libhdf5's plain reader refuse. Opening such a file is not retried once the
superblock has been read.
libhdf5's SWMR reader is looser than either (it reads the fixture's chunk
index past the end of file even with the flags cleared); a test pins what
h5py does and docs/design/swmr.md says why we follow the plain reader.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
clawhdf5.File(path, 'r+') (and 'a' on an existing file) holds a
FileEditor, and with it the file's exclusive lock, until close():
- ds[key] = value: h5py's keys and broadcasting (numpy's rules for
slices and integers with extra leading 1-axes allowed; the exact shape
for an index list, a scalar only where h5py expands it). Arrays are
converted as libhdf5 converts them in native byte order (integers
saturate, floats truncate toward zero and clip, integers go into h5py's
bool enum by value); other values through
numpy.asarray(value, dtype=ds.dtype), as h5py does. NaN into an integer
dataset is a ValueError instead of libhdf5's arbitrary value. The value
preparation is a small Python module compiled into the extension
(src/edit_helpers.py).
- ds.resize(shape) / ds.resize(n, axis=k) with h5py's argument rules.
- attrs[name] = value, attrs.create(name, data, shape, dtype),
attrs.modify: numeric, bool, complex, bytes and str data of any shape,
with h5py's HDF5 types; str is stored as fixed-length UTF-8 (the editor
cannot write variable-length strings).
- File.mode, File.flush(), Dataset.chunks.
Each edit runs with the GIL released under the file handle's write lock
(no read sees a half-written edit), then the file is reopened;
datasets and attrs objects re-read their shape and attributes when the
handle's edit generation moved. What the editor cannot do is
NotImplementedError before anything is written: deleting attributes or
objects, creating datasets or groups, compound fields by name,
variable-length data, and FileEditor's own limits.
Where libhdf5 2.0 (h5py 3.16) converts inconsistently -- its soft
conversions in non-native byte order (a float in (-1, 0) becomes the
integer minimum, same-size unsigned->signed wraps) and native casts that
are undefined in C (half floats into unsigned, float(max) rounded up) --
clawhdf5 saturates as libhdf5's native path does; listed in
docs/known-issues.md.
Tests (tests/test_edit.py): every edit applied by h5py and by clawhdf5 to
copies of the same file and both read back through h5py after each edit,
on h5py files (libver earliest, v114, latest) and a clawhdf5 file: a fixed
sequence over every chunk index kind, compact/contiguous/gzip layouts and
numeric, bool, enum, complex, string and compound types, 16 random
sequences of 40 edits, and a numeric conversion matrix; a refused edit
must be refused by both and leave the file unchanged. Also dense
attributes, locking, objects seeing edits, readers racing a writer, and
h5dump (plus h5rs check in ci-test.sh) on every edited file. The
read-vs-h5py suite also runs on a file opened 'r+'.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
CHANGELOG (Unreleased), known-issues (the browser can open URLs; the
limits of openUrl: round trips per wave of misses, a call holds what it
reads, CORS and validator visibility, the download fallback), the M4
status in docs/design/range-reads.md (why NeedBytes rather than a
Worker, why not clawhdf5-remote's BlockCache, what was tested; the
status paragraph at the top lost a garbled duplicate), the viewer's
README (API, options, how it works, tests; the size table is marked as
predating openUrl), CLAUDE.md and the README crate list.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
The Python bindings could not open a remote file: they parsed through
File::as_bytes() in eight places (path lookups, object headers,
dataspaces, attributes, group listings, the global heap of
variable-length data), which a storage-backed file does not have.
- Every object of a File now shares one handle (src/handle.rs) that
runs all file access, metadata included, with the GIL released and
parses through File::storage() and the clawhdf5_format *_in functions.
Local files take the same path (their storage is the mmap).
- clawhdf5.File(url) opens any scheme://... through
clawhdf5_remote::storage_for_url (read-only; another mode is a
ValueError). File.open_url(url, **options) takes the cache and HTTP
options (block_size, cache_size, headers, retries, timeout,
allow_full_download, max_full_download, require_validator,
max_redirects, max_parallel); File.remote_stats gives the block
cache's counters.
- Default build: plain HTTP only, no C. https (rustls/ring) and
s3/gcs/azure (aws-lc-rs) are opt-in features of clawhdf5-py, and
ci-test.sh's no-C check now covers the crate.
- A failed storage read (network error, file changed on the server) is an
OSError, never KeyError/ValueError and never data; `key in group`
raises it instead of answering False.
Tests: the read-vs-h5py suite runs locally and over HTTP (1 MiB and
1 KiB blocks) against a range-capable http.server in the test process
(conftest.RangeServer); test_remote.py covers request counts, cache
hits, a server without Range support, a changed file, a server that
hangs up, 16 threads, and a spinning thread that keeps running while a
read waits on 0.2 s requests.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
libhdf5's SWMR semantics as they matter to a reader (superblock v3 with
the SWMR-write flag and a stale EOF, append-only writer, flush
dependencies, refresh, 100 metadata read attempts), what clawhdf5 did
with such files, and the plan: data_end bounded by the file length for
SWMR-flagged files, a live File::open_swmr over positioned reads without
the chunk cache, Dataset::refresh, and bounded whole-operation retries.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
An attribute needing a heap block larger than the next one was refused
("skipping blocks too small for an object", "a first object too large for
the starting block"); once an object's move to dense storage was refused
it refused every new attribute, so 24% of set_attr calls in the review's
random workload failed.
Following H5HF__hdr_update_iter, H5HF__man_iblock_root_create/_double and
H5HF__hdr_skip_blocks, the smaller blocks are now skipped: the iterator
moves past them and they become an indirect free section with a first
row section (serialized, class 1, as H5HF__sect_indirect_serialize writes
it) and ghost normal rows, added as returned space so it merges with a
range skipped just before it (H5HF__sect_indirect_merge_row). Later
objects that best-fit a row section get a block created there
(H5HF__man_iblock_alloc_row / H5HF__sect_indirect_reduce_row: from the
start or end of the range, or from its middle, which splits it, with
libhdf5's span bookkeeping). Heaps with such sections, as libhdf5 writes
them, are now read too (they were refused at open).
dense_skipped_blocks_match_libhdf5 drives every path (merge, split, end,
last entry, row wrap) on earliest/v110/latest files against libhdf5
doing the same edits one session each; heaps, free sections and index
B-trees are equal after every phase. The refusal test now checks the
skip against libhdf5 and keeps a real refusal (last object in a block);
clawhdf5-written heaps get 1-4 KiB attributes too. The three tests fail
on the previous fheap.rs. Random workload refusals: 24% -> 2.2%, all the
documented last-object-in-a-block case.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
306 104 and 49 930 are h5repack of the editor's file; the text read as if
they were h5repack of libhdf5's, which measures 305 954 and 50 188. Both
are now given, from measure_append_waste rerun on 2026-09-26 (file sizes
unchanged).
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Our checksum reduced its sums with `% 65535`; libhdf5's
H5_checksum_fletcher32 folds them with `(s & 0xffff) + (s >> 16)`, which
leaves 0xffff where the modulo leaves 0. On about one chunk in 32768
libhdf5 refused the chunks we wrote and we refused the chunks it wrote.
Every release since v2.1.0 is affected.
clawhdf5_format::checksum::fletcher32 is a port of H5_checksum_fletcher32
and the filter's only implementation. Verification also accepts the
byte-swapped form libhdf5 accepts (1.6.2 and earlier) and the `% 65535`
form earlier releases wrote, so their files stay readable.
The new interop test compares the checksum with libhdf5's own function
(ctypes) on every 1- and 2-byte input and 40 000 random and fold-heavy
inputs, and moves fold-case chunks between h5py and FileBuilder/FileEditor
in both directions; with the old filters.rs the three file tests fail.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
CHANGELOG, the clawhdf5-remote and h5rs READMEs and the remote-files
known issues: redirect rules, scaled timeouts (min_speed), URL redaction,
claimed lengths never allocated (download, --max-download), a 200 for a
small file accepted, and ObjectStoreStorage from any thread.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
It refused whenever Handle::try_current() was Ok, which is also the case
inside spawn_blocking threads — so the workaround its own error message
recommended failed the same way, and the backend could only be used from
a bare std::thread in a tokio application.
Reads are now spawned on the storage's own runtime and the caller waits on
a channel: the future never runs on the caller's thread, so neither a
spawn_blocking thread nor a current-thread runtime can deadlock or panic
(a read inside a runtime blocks that thread, like any blocking call; the
docs still recommend spawn_blocking there).
Tests: a read in spawn_blocking of a multi-thread runtime and a read inside
a current-thread runtime's task give File::open's values (both errors
before).
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Only the full read split its chunk fetches into 64 MiB batches. The
selection path, the indexed read and the parallel_read decoders fetched
every chunk's stored bytes in one read_ranges call, each extent bounded only
by the file length, so a crafted chunk index pointing many chunks at one
large extent made File::open_storage hold chunks x extent bytes (3.3 GB from
a 16.8 MB file) before the first decode error.
- storage::for_each_extent_batch is now the one way raw-data reads fetch
chunk bytes: batches of at most RAW_BATCH_BYTES (now pub), each decoded
before the next is fetched. Used by the full, cached, indexed, selection
and parallel_read paths; the sweep read uses read_extent per chunk.
- ExtentReq carries each chunk's claimed extent (bounds-checked as before,
same errors) and the prefix actually fetched:
filters::stored_chunk_limit — the chunk size if unfiltered, else each
applied filter's worst-case growth (n + n/4 + 4096 per codec; unbounded
only for an application-registered codec). The in-memory path cuts the
slice it decodes the same way, so both paths still agree.
- tests/raw_fetch_bounds.rs: a crafted chunked_large.h5 (ten chunks all
claiming 20 MiB at one padding blob) read through every path over a
storage that records the largest single fetch; and 160 MiB of legitimate
unfiltered chunks fetched batch by batch. Before: one 80 MiB fetch
(selection) and one 160 MiB fetch; after: within the budget.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
README: "Reading remote files" (open_url, the range_server and read_url
examples with their real output against the fixtures, h5rs on URLs), the
crate in the crate map and the unreleased highlights. CHANGELOG: the
clawhdf5-remote crate, h5rs URLs, File::storage and
VlResolver::element_in, with the request counts over the conformance
corpus (tank, 2026-09-26, the command given). known-issues: the M2
range-read entry updated (the cache now exists; h5rs reads through
storage) and a new entry for the remote backends' limits (no Python or
browser URLs yet, fixed block size, cloud stores not run against a real
bucket, validators, credentials). Design doc: M3 status with the choices
that differ from the plan (a crate rather than a clawhdf5-io feature,
ureq for HTTP so the default build has no C) and the corpus counts.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
CHANGELOG (Unreleased): the new FileEditor operations, space reuse, and
the two reader fixes (implicit index grid, object-header continuation
chains). known-issues: the editor's remaining refusals (skipped heap
blocks, heaps with filters or child indirect blocks, freeing a heap
block, implicit-index insertions, ...) and the append-waste sizes before
and after reuse (measure_append_waste, tank 2026-09-26; file sizes are
deterministic). range-reads design: status note on the reader changes.
README and CLAUDE.md: what the editor covers and how to test it.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
CHANGELOG (Unreleased): File::open_storage, raw data and v2 B-trees over
Storage, the tests and their corpus results (2026-09-26, tank; conformance
600 of 697, results.json identical to 8f59b2e). known-issues: what
open_storage does not do yet (no remote backend or block cache, read_at
counts of a one-pass read, v1 group lookups, whole-file VDS sources,
zero-copy methods, SWMR growth, hash-order error choice on damaged chunked
datasets). Design: M2 status and the choices made.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
FileBuilder stored every chunk of an LZF or Blosc dataset through the
filter with filter mask 0. libhdf5 counts LZF and Blosc output no smaller
than the chunk as a failure of the optional filter and stores the chunk raw
with the filter's mask bit set. For an LZF chunk whose stream was exactly
the chunk's size, the first libhdf5 rewrite stored raw data at the same
size and kept our stale mask 0 in the index, and h5py could no longer read
the dataset.
precompress_chunks now runs chunks through compress_chunk_masked (as
FileEditor does since f7e2ab1), sequentially and on the parallel path, and
build_chunked_data_from_precompressed records each chunk's real mask in
every index the writer builds: single chunk (layout field), Fixed Array and
Extensible Array filtered elements, and version-2 B-tree type 11 records
(create_datasets_parallel goes through the same path). The writer builds
no version-1 B-tree or implicit index. PrecompressedChunks::chunks gains
the mask. Files whose chunks all compress are byte-identical.
Latent only in the unreleased LZF/Blosc writer (added 2026-09-26); no
tagged release writes either filter.
Tests:
- plugin_filters_interop skipped_optional_filters_are_masked_as_libhdf5_masks_them:
LZF, shuffle+LZF+fletcher32 and Blosc over random, compressible and
alternating chunks in every index; masks equal an h5py-written twin's;
h5py r+ rewrites and extends them; h5py, h5dump and our reader read
every value. Before: 20 of 24 datasets had masks other than h5py's, and
with that check disabled h5py failed to read the rewritten datasets
("filter returned failure during read").
- plugin_filters_interop files_whose_chunks_all_compress_are_unchanged:
pins the pre-fix bytes of five all-compressing files.
- chunked_write skipped_lzf_chunks_are_masked_in_every_index (fails before:
mask 0, want 2).
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
- Per-file probe output is identical for 696 of 697 files, not all:
cve-2025-2310.h5's error string depends on which parallel chunk decode
fails first, at f2ff2c4 as on this branch.
- The parser cores are generic (S: Storage + ?Sized); provisional A/B
numbers against f2ff2c4, including the one bench that still shows
ObjectHeader::parse slower when old and new are separate binaries.
- Reads sized by untrusted fields are bounded; the harness only accepts
the known whole-file fallbacks.
- range-reads.md records why M1 went generic rather than &dyn.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
A dataset whose filter this build cannot encode (scale-offset, N-Bit, SZIP;
a plugin filter the build lacks) failed with Error::Format("unsupported
filter: 6"), although the editor documents every refused edit as
Error::Unsupported, and the Python bindings raised ValueError rather than
NotImplementedError. Every edit now maps FormatError::UnsupportedFilter to
Error::Unsupported; the file is left untouched as before.
Test: edit_interop unencodable_filters_are_unsupported — h5py scale-offset
datasets (integer with chunks, integer never written, float D-scale):
Error::Unsupported naming the filter, and the file byte for byte unchanged.
Fails on the previous editor (Format(UnsupportedFilter(6))).
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Three `chunk_info.address as usize` casts behind the `parallel` feature
survived the conversion, because check-32bit-casts.sh linted only default
features plus plugin-filters. On a 32-bit target with rayon a chunk address
past 4 GiB still wrapped onto another part of the file. They go through
addr::to_usize now, and the lane index (h % n, always < n) through
saturating_usize.
The script now lints no default features, default features, and every
optional feature but szip (wasm32; the set with zstd, which does not build
for wasm32, on the host, where the lint reports the same casts). With the
old parallel_read.rs/lane_partition.rs it fails listing the four casts; the
old script passed them. CHANGELOG and the design note give the exact count
(119) and what is not covered.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
known-issues records what the editor refuses, that freed space is never
reused (append-workload file sizes measured 2026-09-26 on tank with the
ignored measure_append_waste test; sizes are deterministic), and that there
is no journal.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Lists the parsers now reading through Storage, what still needs the
whole file (v2 B-tree-indexed structures: a clean error; raw data: M2),
the equivalence harness, and the evidence that nothing changed: existing
tests, a byte-identical conformance results.json and per-file probe
output against f2ff2c4, and identical slice-API transcripts over 748
files between the two builds.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
ZFP (32013) was the one plugin filter still listed as UnsupportedFilter.
Conformance on tank, `conformance/run.sh --no-fetch` (2026-09-26): 600 of
697 files ok (baseline 599); h5ex_d_zfp.h5 is newly ok.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Idle-start run on tank at c5334b1 (noisier than the last: compare ratios
within the run). Full reads of deflate data at 16 threads: 4944 MB/s vs
3135 for 16 h5py processes (1.58x; 0.69x-0.76x before). One thread with
the default pool: 6143 MB/s, 15x one h5py call. The concurrent-read
known issue is closed.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
