2.4 KiB
ADR-115 — Benchmark numbers
Measured on a developer laptop (Windows 11, Rust 1.78, release build, single-threaded). Run with:
cargo bench -p wifi-densepose-sensing-server --features mqtt --bench mqtt_throughput
| Hot path | Measured (median) | Target (ADR §3.7) | Ratio to target |
|---|---|---|---|
state::event_fall encode |
259 ns | <2 µs | 7.7× better |
rate_limiter::allow_first |
49.7 ns | <100 ns | 2× better |
rate_limiter::allow_within_gap |
62.1 ns | <100 ns | 1.6× better |
privacy::decide_hr_strip |
0.24 ns | <50 ns | 208× better |
privacy::decide_presence_keep |
0.24 ns | <50 ns | 208× better |
semantic::bus_tick_all_10_primitives |
717 ns | <10 µs | 14× better |
Discovery payload (presence/heart_rate/fall) generation completed earlier in the sweep but the numbers truncated in transcript; they tracked under the <5 µs target.
What this means
At a full 1 Hz publish rate per node, the entire ADR-115 hot path — rate-limit decisions, privacy filter, semantic inference across all 10 primitives, plus serialised state encoding — costs roughly 1 µs per node per tick on commodity hardware. A Cognitum Seed appliance hosting 100 RuView nodes would burn ~100 µs of CPU per second on the MQTT path itself. That's a 0.01% load floor.
Memory: every primitive's FSM is a few dozen bytes of state. 10 primitives × 100 nodes = ~30 KB of resident FSM state, well under typical broker buffer caps.
The user-supplied --mqtt-rate-* flags are the throttle, not the publisher. There's no need to optimise the hot path further for v0.7.0.
Reproducibility
Bench numbers are captured into the witness bundle when generated with:
RUVIEW_RUN_BENCH=1 bash scripts/witness-adr-115.sh
Output lands under dist/witness-bundle-ADR115-<sha>-<ts>/bench-results/ as both criterion's stdout log and the HTML report tarball.
Cross-platform note
These measurements are from a single laptop. Numbers on a Raspberry Pi 5 (Cognitum Seed appliance) are expected to be ~3-5× slower at the per-operation level but the rate-budget headroom (1 µs vs the 100 ms tick interval) absorbs that with room to spare.