perf-benchmarker

name: perf-benchmarker description: "Use when running performance benchmarks, establishing baselines, or validating regressions with sequential runs. Enforces 60s minimum runs (30s only for binary search) and no parallel benchmarks." version: 5.1.0 argument-hint: "[command] [duration]"

Run sequential benchmarks with strict duration rules.

Follow docs/perf-requirements.md as the canonical contract.

Parse Arguments

const args = '$ARGUMENTS'.split(' ').filter(Boolean);
const command = args.find(a => !a.match(/^\d+$/)) || '';
const duration = parseInt(args.find(a => a.match(/^\d+$/)) || '60', 10);

Required Rules

Benchmarks MUST run sequentially (never parallel).
Minimum duration: 60s per run (30s only for binary search).
Warmup: 10s minimum before measurement.
Re-run anomalies.

Output Format

command: <benchmark command>
duration: <seconds>
warmup: <seconds>
results: <metrics summary>
notes: <anomalies or reruns>

Output Contract

Benchmarks MUST emit a JSON metrics block between markers:

PERF_METRICS_START
{"scenarios":{"low":{"latency_ms":120},"high":{"latency_ms":450}}}
PERF_METRICS_END

Constraints

No short runs unless binary-search phase.
Do not change code while benchmarking.