.github/workflows/json_view_benchmarks.yml

name: "json_view benchmarks"

# On demand only: runs the comparison of json_view with yyjson, simdjson, and
# Boost.JSON (tests/benchmarks/json_view/compare.py) on GitHub-hosted runners,
# for numbers from x86-64 and AArch64 Linux. It runs when started by hand, or
# when a pull request gets the label "benchmark" (on both architectures, with
# GCC and the default settings). Shared runners are noisy: the results show
# where json_view stands, but published numbers need a quiet machine (see
# tests/benchmarks/json_view/README.md).

on:
  pull_request:
    types: [labeled]
  workflow_dispatch:
    inputs:
      runner:
        description: "Runner image"
        type: choice
        options:
          - ubuntu-24.04
          - ubuntu-24.04-arm
        default: ubuntu-24.04
      compiler:
        description: "Compiler"
        type: choice
        options:
          - g++
          - clang++
        default: g++
      native:
        description: "Compile for the runner's CPU (-march=native)"
        type: boolean
        default: false
      rounds:
        description: "Rounds of bench_view"
        type: number
        default: 30

permissions:
  contents: read

concurrency:
  # (the label is part of the group: adding an unrelated label must not cancel a running benchmark)
  group: json-view-benchmarks-${{ github.workflow }}-${{ github.ref }}-${{ github.event.label.name }}
  cancel-in-progress: true

jobs:
  compare:
    if: github.event_name == 'workflow_dispatch' || github.event.label.name == 'benchmark'
    strategy:
      matrix:
        runner: ${{ fromJSON(github.event_name == 'workflow_dispatch' && format('["{0}"]', inputs.runner) || '["ubuntu-24.04", "ubuntu-24.04-arm"]') }}
    runs-on: ${{ matrix.runner }}
    timeout-minutes: 60
    steps:
      - name: Harden Runner
        uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
        with:
          egress-policy: audit

      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          persist-credentials: false

      - name: Download test data
        run: |
          cmake -S . -B build -DJSON_BuildTests=On
          cmake --build build --target download_test_data

      - name: Run the comparison
        env:
          CXX: ${{ inputs.compiler || 'g++' }}
          CC: ${{ inputs.compiler == 'clang++' && 'clang' || 'gcc' }}
          ROUNDS: ${{ inputs.rounds || 30 }}
          NATIVE: ${{ inputs.native && '--native' || '' }}
        run: python3 tests/benchmarks/json_view/compare.py --data build/test_files --download --rounds "$ROUNDS" $NATIVE

      - name: Summary
        run: cat tests/benchmarks/json_view/results/*.md >> "$GITHUB_STEP_SUMMARY"

      - uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
        with:
          name: json_view-benchmarks-${{ matrix.runner }}-${{ inputs.compiler || 'g++' }}
          path: tests/benchmarks/json_view/results/