bench

name	bench
description	Run emitrix performance checks — throughput benchmark and stress suite — and judge regressions against recorded baselines. Use for performance questions and before merging changes to dispatch, ListenerStore, or the middleware chain.

Benchmarking emitrix

1. npm run build (benchmark runs against dist/)
2. node benchmarks/loadTest.js — 1M awaited emits across 4 listeners (incl. one wildcard)
3. npm run test:stress — memory soak with leak bounds, seeded fuzz, concurrency storms

Baselines (2026-07, Apple-silicon dev machine, Node 22)

• Benchmark loop: ~700 ms for 1M awaited emits
• ~600 ns/emit with envelope + middleware + 4 mixed listeners (~1.6M emits/s/core)
• Plain emit, 4 exact listeners: ~570 ns; parallel dispatch, 8 async listeners: ~840 ns
• Subscribe+unsubscribe churn: ~300 ns with 100 standing listeners, ~1.3 µs at 1k, ~11.7 µs at 10k — linear O(n) growth is expected and accepted (emit-heavy workload trade-off)
• 10k concurrent waitFor resolved by one emit: ~75 ms total

Interpreting regressions

• 2x slower on the benchmark loop: look at ListenerStore.collect (the wildcard path concat+sort) and the middleware reduceRight chain first.

• Soak-test heap growth over its 10 MB bound: something is retaining per-subscription state — check timer sets and detachSignal cleanup.
• Fuzz failures print their seed — rerun is deterministic; do not shrug them off as flakes, they never are.