develop has been over the 746 000 line since #11826 (748 088 on the
CI runner at 3468af94a), so the size-budget-gate fails on every PR that
does not itself shed 2 KB, and the queue behind it cannot land. 6 KB
covers the current overage plus the pending NodeDB/NodeInfo work
(+584) and one or two of the mid-sized branches, while staying 47 KB
inside the 0xEA000 warm-region guard that is the real wall (image ends
at 0xDCA38 today). Raised deliberately, per the file's own rule.
* Remove proprietary Bosch BSEC blob; open in-tree IAQ estimator for BME680
BSEC2 cost ~37-39 KB flash and ~4-5 KB static RAM on ~190 of ~240 build
targets, linked whether or not a BME680 was attached, and was a no-source
proprietary archive inside GPLv3 release binaries. The firmware consumed
exactly one BSEC-exclusive output: the IAQ value.
- New BME680IaqEstimator: clean-room log-domain baseline tracker
(humidity-compensated gas resistance vs a rise-fast/decay-slow ceiling,
0-500 scale matching the existing UI bands), pure math, unit-tested on
native (test_bme680_iaq, 15 tests incl. a deep-sleep reboot simulation).
Warm-up/burn-in progress persists to /prefs/bme680.dat via SafeFile so
one-sample-per-wake SENSOR nodes converge across reboots; stale
/prefs/bsec.dat is removed once.
- BME680Sensor: single-path rewrite on Adafruit_BME680 with async
once-per-minute sampling (~20x lower heater duty than BSEC LP mode),
a hard 2-minute publish-freshness bound (a dead sensor stops reporting
instead of freezing its last reading on the wire), and suppression of
bogus gas_resistance=0 points from heater-unstable cycles.
- platformio.ini: environmental_extra_common/_extra/_no_bsec collapsed
into one section; Bosch BSEC2 + BME68x deps deleted; per-variant BSEC
link-path hacks and the TEMPORARY promicro lib_ignore removed.
nrf52_promicro_diy_tcxo regains BME680 support at 36 KB clear of the
warm-store cap; rak4631 lands at 75 KB clear.
- EnvironmentTelemetry: iaq rendering gates on has_iaq (a genuine IAQ of
0 now displays); stale BSEC comments rewritten.
- rak4631 size budgets tightened (113000->108000 RAM, 786000->746000
flash) to lock in the reclaimed headroom.
- bin/bme680_iaq_replay.cpp: host-side replay harness for tuning the
estimator against captured BSEC traces (mean abs error + band
agreement), no reflashing needed.
Measured (develop -> this branch): rak4631 -38.8 KB flash / -4.9 KB RAM;
heltec-v3 -36.4 KB / -4.0 KB; tlora-v2-1-1_6 +1.3 KB (its IAQ
approximation had been dead code since #9663 due to an inverted isfinite
check and now actually runs).
Note: gas_resistance stays kOhm on the wire for fleet compatibility; the
proto comment claiming MOhm gets a separate meshtastic/protobufs docs PR.
* Address CodeRabbit review feedback
- Use Throttle::isWithinTimespanMs for all elapsed-time predicates in
BME680Sensor per coding guidelines (deadline math for the async reading
completion stays raw, as it targets an absolute timestamp)
- Make the state file name members static constexpr
- Replay tool: cast uint16_t before %u (default argument promotion), report
malformed input lines instead of silently skipping, and fail non-zero on
stream read errors
* Address CodeRabbit nitpicks
- Replace the local clampf helper with std::clamp (meshUtils.h's clamp drags
in Arduino.h, which would break the estimator's standalone host build that
the replay harness depends on)
- Trim the replay tool's file header to a two-line summary; the full build,
capture, and tuning workflow moves to docs/bme680_iaq_replay.md
* CI: track RAM (.data+.bss) in size reports and gate on per-env budgets
The 2.8.0 nRF52840 heap regression (99% heap in field reports) shipped
invisibly because CI only tracked flash. On nRF52840 the heap arena is the
linker gap after .bss, so every byte of static .data+.bss growth shrinks the
usable heap 1:1 - RAM needs the same guardrails flash already has.
What's added:
- bin/platformio-custom.py emits ram_bytes (.data + .bss from the ELF, via
the toolchain size tool) into each .mt.json manifest. Heap/stack
placeholder sections are deliberately excluded.
- bin/collect_sizes.py records {flash_bytes, ram_bytes} per env;
bin/size_report.py grows RAM and RAM-delta columns in the PR size report.
Older artifacts without ram_bytes (and legacy int-schema baselines)
degrade to "n/a" instead of crashing.
- bin/ram_budgets.json: per-env RAM/flash budgets, enforced only for envs
listed there. Seeded with rak4631: ram 113,000 (current 110,948 + ~2 KB
slack), flash 786,000 (current 765,192 + ~20 KB; the app region is
0x27000..0xEA000 = 798,720 and the image must stay clear of the
warm-store ring guard in extra_scripts/nrf52_warm_region.py).
- New size-budget-gate CI job runs size_report.py --enforce-budgets and
fails the build on violation; the informational firmware-size-report job
now also renders budget usage into the PR comment.
- src/main.cpp: opt-in boot heap watermark (-DMESHTASTIC_HEAP_WATERMARK_CHECK)
logs LOG_ERROR when less than 20% of the heap is free at the end of
setup(). Off by default; skipped on platforms without heap accounting.
How budgets are raised: deliberately, never automatically. If a change needs
more headroom, bump the env's limit in bin/ram_budgets.json in the same PR
and justify the increase in the PR description.
Verified: python3 bin/test_size_scripts.py (23/23 pass, including ram_bytes
parsing, n/a fallback, and over/under/missing-env budget-gate cases).
* Address review: fail the budget gate closed, fix RAM section matching
- size-budget-gate workflow: drop continue-on-error on the manifest
download and the empty-dir fallback, so the job fails when the data it
gates on cannot be fetched.
- size_report.py --enforce-budgets now fails closed on every
missing-data path instead of trivially passing: empty collected sizes,
a budgeted env that was not built, or a manifest without the budgeted
metric. Report-only mode keeps rendering those as n/a.
- load_budgets() rejects zero/negative/non-integer budgets with a clear
error (a typo'd budget could previously crash budget_markdown with
ZeroDivisionError or silently skip the check); the percentage render
keeps a defensive guard for direct callers.
- compute_ram_bytes(): count RISC-V small-data sections (.sdata/.sbss)
and exclude ESP-IDF .rtc.* sections, which live outside the
heap-competing SRAM.
- Trim the heap-watermark comment in main.cpp to two lines.
bin/test_size_scripts.py: 27/27 - the two fail-open assertions are
flipped to fail-closed, with new report-only counterparts plus cases for
empty sizes under enforcement and malformed budgets.
Tom