Matched Hemera feature performance — prepared, timing held
The source/tool/build preflight passes. No benchmark has executed in this investigation. Root review of the freeze is complete; the accepted finite schedule awaits an explicitly coordinated quiet window. Active unrelated compute currently prevents that window. The historical initial 5/9 and repeat 6/9 red threshold crossings remain red/unverified.
The accepted plan was committed
as edba749; owning compiler inputs remain fixed at
64d091e5ad3f277cce77b88ae0de6eea4c49b4df. No owning production, dependency,
lockfile, version or benchmark source was edited. All commands below take the
owning repository argument. Their complete argv, paths, hashes and streams are
retained beside this report.
The post-merge source bridge records production changes
in master at 262de214. C/D remains scoped to the frozen 64d091e5 inputs;
no current-master performance result is established.
Inputs and builds
nu prepare-sources.nu REPO CACHE reproduces the exact historical capsules,
accepted patch and current committed exports in sources.json.
A uses Nox 0b1407a4…, Hemera d5f0a095…, Strata 494df7a0…, Lens
8b26cef6…; B differs only by the accepted two-file patch. C/D use Nox
64d091e5…, Hemera 1c385e54…, Strata 56aedb2d… and the same Lens revision.
C's exported manifest reverses only the two feature edits; D retains the shipped
policy. P has A's exact bodies and modes at a different same-depth cache path.
nu prepare-registry.nu REPO CACHE CARGO_CACHE verifies all 72 locked package
archives against lock checksums, extracts every member and freezes the directory
source checksums. registry.json records the sole configuration
change from the original registry setup: its cache-local path relocation.
build.nu and finish-builds.nu build each cell
exactly once using the original locked/offline benchmark command with --no-run,
-vv and Cargo JSON output. env -i applies the recorded allowlist; rustup
1.95.0, absolute RUSTC/RUSTDOC, two jobs, no incremental compilation and empty
Rust flags are identical across cells. Target identity is aarch64-apple-darwin.
tools.json records executable/sysroot hashes, compiler/linker/SDK,
OS and hardware observations. Full Xcode is unavailable; the recorded command
line tools and SDK are available. The historical host is not reconstructed.
builds.json retains all five successful build receipts and binary
hashes. Every binary is 3,044,656 bytes. Feature trees and actual rustc cfg/command
lines show inherited Hemera default,std in A/C/P and their absence in B/D.
No timed invocation is allowed to compile or change its frozen binary.
Source and code bridges
nu summarize-preflight.nu REPO at the source revisions above produces
preflight-summary.json. B/D changes 45 Nox Rust files
and two Strata Rust files. Hemera and Lens compiler-source bytes match between
eras. The benchmark's complete diff is formatting:
pinned rustfmt on historical bytes produces the exact current bytes, recorded
in benchmark-format.json. Strata's algebra_impl.rs
and proptests.rs differ materially, including the Dot implementation. B/D
therefore remains a multi-source comparison; this investigation repairs none
of those source changes.
nu inspect.nu REPO CACHE compares all 17 Mach-O sections and all 3,949
LC_FUNCTION_STARTS spans per binary. code.json binds the exact
raw sections, complete disassembly and explicit normalized view to each binary.
Span lengths include any padding up to the next start; semantic function sizes
and complete reachable call boundaries remain unknown. Cargo's raw rustc/link
driver commands are retained; child linker argv was not instrumented.
| Contrast | Label-selected spans | Unique name matches | Exact raw span matches | Moved spans |
|---|---|---|---|---|
| A/B, historical feature policy | 49 | 47 | 35 | 5 |
| C/D, current feature policy | 49 | 47 | 16 | 29 |
| A/P, identical-source path control | 49 | 47 | 44 | 2 |
| B/D, source-era bridge | 49 | 47 | 22 | 26 |
Each contrast changes raw __text, constants and unwind-related sections,
including A/P. Cache-path/layout effects therefore exist in this build setup.
Whole-file inequality or selected span equality cannot isolate a feature effect,
prove complete equivalence or establish the cause of the old performance reds.
Portable replay and timing boundary
inputs.tar.gz, indexed by inputs.json, retains
the exact source archives, treatment bodies, registry archives/checksums, five
binaries, every raw section and helper binaries. Its SHA256 is
da606913e228eacd0687d3691529ee231d7e3b72327e07020fa2facbf5e75231.
The read-only verifier extracts its own temporary directory and checks the
archived bytes without executing archived helper binaries or historical Ruby:
--live additionally checks the original cache and current tool executables.
preflight.json records a successful portable-plus-live replay;
the final freeze also records the exact verifier inputs for its final replay.
The named thumb gate passes after the pinned-path correction. Its initial
missing-core red, the already-installed target observation, all preparation
failures and successful rerun remain in preparation.md.
Broad hygiene tests were bridged by exact compiler-input bytes, not rerun.
timing.nu requires a separate root authorization bound to the exact
freeze and approving a quiet window. It permits exactly
A1 B1 B2 A2 C1 D1 D2 C2, a 60-second idle interval, then
D3 C3 C4 D4 B3 A3 A4 B4. Every run preserves all nine complete Criterion
directories, raw streams, median 95% intervals and a fixed five-second sampler.
Missing or stale cases, rebuilds or source/tool/binary drift stop the schedule
without replacement. No CPU affinity or frequency control is claimed.
After that schedule, verify.nu REPO --timed computes every individual
comparison from estimates.json: 36 per source era and 72 same-binary temporal
case comparisons. The original rule is unchanged: candidate/parent median
greater than 1.05, or candidate lower median bound above parent upper bound.
Independent telemetry review is still required to assess host interference.
A green future contrast cannot erase the old reds or identify their cause.