benchmarks.yml

# Continuous benchmarking with Bencher (https://bencher.dev)
#
# PREREQUISITES:
#   1. Create a project at https://bencher.dev and note its slug.
#   2. Add the following secrets in GitHub → Settings → Secrets and variables → Actions:
#      - BENCHER_API_TOKEN: API token from bencher.dev
#      - BENCHER_PROJECT:   your project slug
#   3. GITHUB_TOKEN is provided automatically — no setup needed.
#
# overhead_bench uses a custom harness (not Criterion). Its --bmf flag
# outputs Bencher Metric Format directly.

name: Benchmarks

on:
  push:
    branches:
      - main
  pull_request:
  workflow_dispatch:

permissions:
  checks: write
  pull-requests: write

jobs:
  # Runs on every push to main to build the statistical baseline.
  benchmark_main:
    name: Benchmark (main baseline)
    if: github.event_name == 'push' || github.event_name == 'workflow_dispatch'
    runs-on: ubuntu-latest
    timeout-minutes: 30
    env:
      RUST_BACKTRACE: 1
      BENCHER_PROJECT: ${{ secrets.BENCHER_PROJECT }}
    steps:
      - uses: actions/checkout@v4
      - uses: dtolnay/rust-toolchain@stable
      - uses: Swatinem/rust-cache@v2

      - name: Enable perf_event_open and kallsyms
        run: |
          sudo sysctl kernel.perf_event_paranoid=1
          sudo sysctl kernel.kptr_restrict=0

      - uses: bencherdev/bencher@main

      - name: Benchmark — poll_overhead
        run: |
          bencher run \
            --token '${{ secrets.BENCHER_API_TOKEN }}' \
            --branch '${{ github.ref_name }}' \
            --testbed ubuntu-latest \
            --adapter rust_criterion \
            "cargo bench --package dial9-tokio-telemetry --bench poll_overhead --features task-dump"

      - name: Benchmark — writer_encode
        run: |
          bencher run \
            --token '${{ secrets.BENCHER_API_TOKEN }}' \
            --branch '${{ github.ref_name }}' \
            --testbed ubuntu-latest \
            --adapter rust_criterion \
            "cargo bench --package dial9-tokio-telemetry --bench writer_encode"

      - name: Benchmark — codec
        run: |
          bencher run \
            --token '${{ secrets.BENCHER_API_TOKEN }}' \
            --branch '${{ github.ref_name }}' \
            --testbed ubuntu-latest \
            --adapter rust_criterion \
            "cargo bench --package dial9-trace-format --bench codec"

      - name: Benchmark — overhead_bench
        run: |
          bencher run \
            --token '${{ secrets.BENCHER_API_TOKEN }}' \
            --branch '${{ github.ref_name }}' \
            --testbed ubuntu-latest \
            --adapter json \
            "cargo bench --bench overhead_bench -- --bmf 10"

      - name: Benchmark — e2e_workload
        run: |
          bencher run \
            --token '${{ secrets.BENCHER_API_TOKEN }}' \
            --branch '${{ github.ref_name }}' \
            --testbed ubuntu-latest \
            --adapter json \
            "cargo bench --bench e2e_workload -- --bmf 10"

  # Runs on same-repo PRs. Fork PRs are skipped — they have no access to
  # BENCHER_API_TOKEN, so the job would fail rather than silently skip.
  benchmark_pr:
    name: Benchmark (PR regression check)
    if: github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository
    runs-on: ubuntu-latest
    timeout-minutes: 30
    env:
      RUST_BACKTRACE: 1
      BENCHER_PROJECT: ${{ secrets.BENCHER_PROJECT }}
    steps:
      - uses: actions/checkout@v4
      - uses: dtolnay/rust-toolchain@stable
      - uses: Swatinem/rust-cache@v2

      - name: Enable perf_event_open and kallsyms
        run: |
          sudo sysctl kernel.perf_event_paranoid=1
          sudo sysctl kernel.kptr_restrict=0

      - uses: bencherdev/bencher@main

      - name: Benchmark — poll_overhead
        run: |
          bencher run \
            --token '${{ secrets.BENCHER_API_TOKEN }}' \
            --branch '${{ github.head_ref }}' \
            --start-point main \
            --start-point-reset \
            --testbed ubuntu-latest \
            --adapter rust_criterion \
            --threshold-measure latency \
            --threshold-test percentage \
            --threshold-upper-boundary 0.25 \
            --threshold-measure throughput \
            --threshold-test percentage \
            --threshold-lower-boundary 0.25 \
            --error-on-alert \
            --github-actions '${{ secrets.GITHUB_TOKEN }}' \
            "cargo bench --package dial9-tokio-telemetry --bench poll_overhead --features task-dump"

      - name: Benchmark — writer_encode
        run: |
          bencher run \
            --token '${{ secrets.BENCHER_API_TOKEN }}' \
            --branch '${{ github.head_ref }}' \
            --start-point main \
            --start-point-reset \
            --testbed ubuntu-latest \
            --adapter rust_criterion \
            --threshold-measure latency \
            --threshold-test percentage \
            --threshold-upper-boundary 0.25 \
            --threshold-measure throughput \
            --threshold-test percentage \
            --threshold-lower-boundary 0.25 \
            --error-on-alert \
            --github-actions '${{ secrets.GITHUB_TOKEN }}' \
            "cargo bench --package dial9-tokio-telemetry --bench writer_encode"

      - name: Benchmark — codec
        run: |
          bencher run \
            --token '${{ secrets.BENCHER_API_TOKEN }}' \
            --branch '${{ github.head_ref }}' \
            --start-point main \
            --start-point-reset \
            --testbed ubuntu-latest \
            --adapter rust_criterion \
            --threshold-measure latency \
            --threshold-test percentage \
            --threshold-upper-boundary 0.25 \
            --threshold-measure throughput \
            --threshold-test percentage \
            --threshold-lower-boundary 0.25 \
            --error-on-alert \
            --github-actions '${{ secrets.GITHUB_TOKEN }}' \
            "cargo bench --package dial9-trace-format --bench codec"

      - name: Benchmark — overhead_bench
        run: |
          bencher run \
            --token '${{ secrets.BENCHER_API_TOKEN }}' \
            --branch '${{ github.head_ref }}' \
            --start-point main \
            --start-point-reset \
            --testbed ubuntu-latest \
            --adapter json \
            --threshold-measure latency \
            --threshold-test percentage \
            --threshold-upper-boundary 0.25 \
            --threshold-measure throughput \
            --threshold-test percentage \
            --threshold-lower-boundary 0.25 \
            --error-on-alert \
            --github-actions '${{ secrets.GITHUB_TOKEN }}' \
            "cargo bench --bench overhead_bench -- --bmf 10"

      - name: Benchmark — e2e_workload
        run: |
          bencher run \
            --token '${{ secrets.BENCHER_API_TOKEN }}' \
            --branch '${{ github.head_ref }}' \
            --start-point main \
            --start-point-reset \
            --testbed ubuntu-latest \
            --adapter json \
            --threshold-measure latency \
            --threshold-test percentage \
            --threshold-upper-boundary 0.25 \
            --threshold-measure throughput \
            --threshold-test percentage \
            --threshold-lower-boundary 0.25 \
            --error-on-alert \
            --github-actions '${{ secrets.GITHUB_TOKEN }}' \
            "cargo bench --bench e2e_workload -- --bmf 10"