# Golang Benchmark

Golang benchmarking, profiling, and performance measurement.

- Repository: https://github.com/samber/cc-skills-golang (3750 stars)
- Category: Writing
- License: MIT
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add samber/cc-skills-golang --skill golang-benchmark -g -a claude-code -y`
Codex: `npx skills add samber/cc-skills-golang --skill golang-benchmark -g -a codex -y`
Cursor: `npx skills add samber/cc-skills-golang --skill golang-benchmark -g -a cursor -y`
Gemini CLI: `npx skills add samber/cc-skills-golang --skill golang-benchmark -g -a gemini-cli -y`

## Description

Golang benchmarking, profiling, and performance measurement. Use when writing, running, or comparing Go benchmarks, profiling hot paths with pprof, interpreting CPU/memory/trace profiles, analyzing results with benchstat, setting up CI benchmark regression detection, or investigating production performance with Prometheus runtime metrics. Also use when the developer needs deep analysis on a specific performance indicator - this skill provides the measurement methodology, while `samber/cc-skills-golang@golang-performance` provides the optimization patterns.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

**Persona:** You are a Go performance measurement engineer. You never draw conclusions from a single benchmark run, statistical rigor and controlled conditions are prerequisites before any optimization decision.

**Thinking mode:** Reason as thoroughly as possible for benchmark analysis, profile interpretation, and performance comparison tasks, deep reasoning prevents misinterpreting profiling data and ensures statistically sound conclusions. On Claude Code, use `ultrathink` to trigger extended thinking explicitly.

**Dependencies:**

- benchstat: `go install golang.org/x/perf/cmd/benchstat@latest`

# Go Benchmarking & Performance Measurement

Performance improvement does not exist without measures, if you can measure it, you can improve it.

This skill covers the full measurement workflow: write a benchmark, run it, profile the result, compare before/after with statistical rigor, and track regressions in CI. For optimization patterns to apply after measurement, → See `samber/cc-skills-golang@golang-performance` skill. For pprof setup on running services, → See `samber/cc-skills-golang@golang-troubleshooting` skill.

## Writing Benchmarks

### File and Ordering Conventions

Benchmark functions live in a `_bench_test.go` file named after the source file under benchmark, not after the individual function, `parser.go` -> `parser_bench_test.go`, containing `BenchmarkParse`, `BenchmarkEncode`, etc., not a separate `benchmarkparse_test.go` per function.

- Keeping benchmarks in their own file (instead of mixed into `parser_test.go`) keeps `go test -bench=. ./pkg/parser` output free of unrelated `Test*` noise.
- It separates fixtures sized for measurement (large inputs, long-lived setup) from those sized for correctness, the two rarely share the same shape.
- The file still follows Go's one-test-file-per-source-file convention (→ See `samber/cc-skills-golang@golang-testing` skill), just with the `_bench` suffix marking its narrower purpose.

The rest: https://github.com/samber/cc-skills-golang/blob/HEAD/skills/golang-benchmark/SKILL.md