microlp 0.5.0

name: Benchmark

# Manual-only: solves the vendored benchmark instances with microlp and the
# rival solvers (HiGHS, SCIP, Clarabel), then uploads BENCHMARK.md as an
# artifact and renders it in the job summary. Hosted runners are shared
# machines, so absolute times are noisier than a quiet desktop — the
# solver-to-solver comparisons are the durable signal.
on:
  workflow_dispatch:
    inputs:
      time_limit:
        description: "Per-(instance, solver) budget in seconds"
        required: false
        default: "300"
      mip_gap:
        description: "Relative MIP gap all solvers stop at (0 = exact; 0.0001 = 0.01%)"
        required: false
        default: "0.0001"

concurrency:
  group: benchmark
  cancel-in-progress: false

jobs:
  benchmark:
    name: Run benchmark
    runs-on: ubuntu-latest
    timeout-minutes: 350
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      # cmake + a C++ toolchain compile HiGHS from source, libclang feeds its
      # bindgen, and the prebuilt SCIP links against the Fortran runtime.
      - name: Install prerequisites
        run: sudo apt-get update && sudo apt-get install -y cmake build-essential libclang-dev libgfortran5

      - name: Cache Rust
        uses: actions/cache@v4
        with:
          key: ${{ runner.os }}-benchmark-${{ hashFiles('Cargo.lock', 'Cargo.toml', 'benchmark/Cargo.toml') }}
          restore-keys: ${{ runner.os }}-benchmark-
          path: |
            ~/.cargo/registry/index/
            ~/.cargo/registry/cache/
            ~/.cargo/git/db/
            target/

      - name: Build
        run: cargo build --locked -p microlp-benchmark --release

      - name: Run benchmark
        run: |
          set -o pipefail
          cargo run --locked -p microlp-benchmark --release -- \
            --time-limit "${{ inputs.time_limit }}" \
            --mip-gap "${{ inputs.mip_gap }}" \
            --out BENCHMARK.md 2>&1 | tee benchmark-progress.log

      - name: Publish report to the job summary
        run: cat BENCHMARK.md >> "$GITHUB_STEP_SUMMARY"

      - name: Upload artifact
        uses: actions/upload-artifact@v4
        with:
          name: benchmark-report
          path: |
            BENCHMARK.md
            benchmark-progress.log
          if-no-files-found: error