Duty-cycle throttling, CAD-under-load, capture decoupling, remote admin under
throttle, and radio-watchdog fire/recover all device-confirmed on a Heltec
V4.2 (busy mesh + off-frequency bench). Notes the watchdog observability
gotchas found during testing: silent on release builds (check stats-radio-diag
err_flags bit 8) and armed only after first radio activity.
Device testing at 'set dutycycle 1' on a busy mesh showed the node becoming
un-administrable within ~2 minutes: the shed policy dropped its own CLI
responses along with repeats, and parked retransmissions (which never expire)
absorbed every budget refill.
RxReservePacketManager now sheds by priority below the RX reserve — only
pri > 1 outbound (multi-hop flood repeats, adverts, trace) is refused, so the
node's own responses/ACKs (pri 0) and login/PATH replies (pri 1) still queue;
below an emergency floor (reserve/2) everything is shed to protect capture.
Queued packets untransmitted 30 s past their scheduled time are expired at
dequeue via a pointer-keyed age table (the pool is a fixed set of packets, so
pool_size slots cover every key). Under normal load the queue drains in
milliseconds and neither policy triggers.
Load-testing the restored token bucket at 'set dutycycle 1' showed MQTT
capture dropping to exactly the TX rate. Queued retransmissions hold static-
pool packets with no expiry, so throttling parks the whole pool in the send
queue; Dispatcher::checkRecv() then discards received packets before logRx()
ever feeds the bridge — each completed TX frees exactly one packet for
exactly one more RX.
Observer builds now use RxReservePacketManager (fork-owned header): once the
free pool drops below a quarter of the pool, outbound packets are refused and
freed, so RX allocation and MQTT capture continue at full rate while the node
sheds repeat load it has no TX budget for anyway. Non-observer builds keep
upstream pool behavior via the same factory; StaticPoolPacketManager stays
byte-identical to upstream.
Commit 22eb9b87 ("Revert 'Merge remote-tracking branch origin/dev...'")
reverted an entire upstream merge to escape a bad merge state, dropping
860 lines across 66 files. Among the collateral never reconciled on a
later re-merge was eb4fa032's token-bucket duty-cycle enforcement — the
mechanism that keeps nodes under a configured airtime budget (and EU
868 MHz nodes under the legally-mandated duty cycle). The fork had fallen
back to fixed per-packet spacing (getAirtimeBudgetFactor reverted to 2.0),
losing the windowed enforcement.
This was never an intentional design choice, so restoring it re-aligns the
fork with upstream and REDUCES the merge-conflict surface: Dispatcher.{h,cpp}
now diverge from upstream by watchdog additions only (77 insertions, 0
deletions) instead of rewriting checkSend()/loop().
Restored from upstream: updateTxBudget/tx_budget_ms/duty_cycle_window_ms/
getRemainingTxBudget/getDutyCycleWindowMs and the windowed budget logic in
Dispatcher; getOutboundTotal() and the 0xFFFFFFFF count-all sentinel in
StaticPoolPacketManager; the getOutboundTotal() call in StatsFormatHelper.
Re-applied the fork's MQTT radio-watchdog on top as pure additions
(#ifdef WITH_MQTT_BRIDGE), keeping formatRadioDiag.
Stored airtime_factor settings keep their meaning: fork's t*factor spacing
and upstream's 1/(1+factor) windowed budget yield the same steady-state
duty cycle; upstream additionally allows short bursts within the window.
Phase 2 (CAD / radio_fem_rxgain, which touch NodePrefs persistence and
per-board FEM wiring) is documented in RESTORE_UPSTREAM_NOTES.md, not done
here. Builds: Heltec_v3 observer + plain repeater. NEEDS ON-DEVICE
duty-cycle validation before merge.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>