bench.yml

name: Bench
on:
  push:
  pull_request:
  workflow_call:
env:
  CARGO_PROFILE_BENCH_BUILD_OVERRIDE_DEBUG: true
  CARGO_PROFILE_RELEASE_DEBUG: true
  CARGO_TERM_COLOR: always
  RUST_BACKTRACE: 1
  TOOLCHAIN: nightly

jobs:
  bench:
    name: Benchmark
    runs-on: self-hosted
    defaults:
      run:
        shell: bash

    steps:
      - name: Install Rust
        uses: dtolnay/rust-toolchain@master
        with:
          toolchain: $TOOLCHAIN
          components: rustfmt

      - name: Install sccache
        uses: mozilla-actions/sccache-action@v0.0.4

      - name: Configure Rust
        run: |
          echo "RUSTFLAGS=-C link-arg=-fuse-ld=lld -C link-arg=-Wl,--no-rosegment" >> "$GITHUB_ENV"
          echo "SCCACHE_GHA_ENABLED=true" >> "$GITHUB_ENV"
          echo "RUSTC_WRAPPER=sccache" >> "$GITHUB_ENV"
          cargo install flamegraph

      - name: Checkout
        uses: actions/checkout@v4

      - name: Fetch NSS and NSPR
        run: |
          hg clone https://hg.mozilla.org/projects/nspr "$NSPR_DIR"
          hg clone https://hg.mozilla.org/projects/nss "$NSS_DIR"
          echo "NSS_DIR=$NSS_DIR" >> "$GITHUB_ENV"
          echo "NSPR_DIR=$NSPR_DIR" >> "$GITHUB_ENV"
        env:
          NSS_DIR: ${{ github.workspace }}/nss
          NSPR_DIR: ${{ github.workspace }}/nspr

      - name: Build
        run: |
          cargo +$TOOLCHAIN bench --features bench --no-run
          cargo +$TOOLCHAIN build --release --bin neqo-client --bin neqo-server
          echo "LD_LIBRARY_PATH=${{ github.workspace }}/dist/Debug/lib" >> "$GITHUB_ENV"

      # Disable turboboost, hyperthreading and use performance governor.
      - name: Prepare machine
        run: |
          sudo /root/bin/prep.sh
          echo "PERF_CMD=record -o perf.data -F997 --call-graph dwarf,16384 -g" >> "$GITHUB_ENV"

      # Pin the benchmark run to core 0 and run all benchmarks at elevated priority.
      - name: Benchmark
        run: |
          nice -n -20 taskset -c 0 \
            cargo +$TOOLCHAIN bench --features bench | tee output.txt

      # Pin the transfer benchmark to core 0 and run it at elevated priority inside perf.
      # Work around https://github.com/flamegraph-rs/flamegraph/issues/248 by passing explicit perf arguments.
      - name: Perf transfer benchmark
        run: |
          nice -n -20 taskset -c 0 \
            cargo +$TOOLCHAIN flamegraph -v -c "$PERF_CMD" --features bench --bench transfer -- \
              --bench --exact "Run multiple transfers with varying seeds"

      - name: Benchmark a client/server transfer
        run: |
          mkdir server && \
            cd server && \
            nice -n -20 taskset -c 0 \
            cargo +$TOOLCHAIN flamegraph -v -c "$PERF_CMD" \
              --bin neqo-server -- $HOST:4433 &
          PID=$!
          mkdir client && \
            cd client && \
            nice -n -20 taskset -c 1 \
            cargo +$TOOLCHAIN flamegraph -v -c "$PERF_CMD" \
              --bin neqo-client -- --output-dir . https://$HOST:4433/$SIZE
          kill $PID
          [ "$(wc -c < client/"$SIZE")" -eq "$SIZE" ] || exit 1
        env:
          HOST: localhost
          SIZE: 7654321

      # Re-enable turboboost, hyperthreading and use powersave governor.
      - name: Restore machine
        run: sudo /root/bin/unprep.sh
        if: success() || failure()

      - name: Download previous benchmark results
        uses: actions/cache@v4
        with:
          path: ./cache
          key: ${{ runner.os }}-benchmark

      # TODO: Wait for this action to be allowlisted. And then figure out how to only upload
      # benchmark data when the main branch is being updated (e.g., if: ${{ github.ref == "refs/heads/main" }})
      # - name: Store current benchmark results
      #   uses: benchmark-action/github-action-benchmark@v1
      #   with:
      #     tool: 'cargo'
      #     output-file-path: output.txt
      #     external-data-json-path: ./cache/benchmark-data.json
      #     fail-on-alert: true
      #     github-token: ${{ secrets.GITHUB_TOKEN }}
      #     comment-on-alert: true
      #     summary-always: true

      - name: Convert for profiler.firefox.com
        run: |
          perf script -i perf.data -F +pid > transfer.perf &
          perf script -i client/perf.data -F +pid > client.perf &
          perf script -i server/perf.data -F +pid > server.perf &
          wait
          mv flamegraph.svg transfer.svg
          mv client/flamegraph.svg client.svg
          mv server/flamegraph.svg server.svg
          rm neqo.svg

      - name: Archive perf data
        uses: actions/upload-artifact@v4
        with:
          name: ${{ github.head_ref || github.ref_name }}-perf
          path: |
            *.svg
            *.perf
            output.txt
            target/criterion
          compression-level: 9