add benchmarking in CI

Author: m-fila

.github/workflows/benchmark.yml

@@ -0,0 +1,47 @@
+name: Benchmark
+on:
+  pull_request:
+    branches:
+      - main
+permissions:
+  pull-requests: write    # action needs to post a comment
+
+jobs:
+  benchmark:
+    name: Julia ${{ matrix.version }} - ${{ matrix.platform.os }} - ${{ matrix.platform.arch }} - ${{ github.event_name }}
+    runs-on: ${{ matrix.platform.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        platform:
+          - os: ubuntu-latest
+            arch: x64
+          - os: ubuntu-24.04-arm
+            arch: aarch64
+        version:
+          - '1'
+          - 'lts'
+    steps:
+      - uses: actions/checkout@v4
+      - uses: julia-actions/setup-julia@v2
+        with:
+          version: ${{ matrix.version }}
+          arch: ${{ matrix.platform.arch }}
+      - uses: julia-actions/cache@v2
+      - uses: julia-actions/julia-buildpkg@v1
+        run: |
+          julia --project=benchmark -e 'import Pkg; Pkg.develop(".."); Pkg.instantiate()'
+          julia --project=benchmark benchmark/benchmarks.jl benchmark/output.json
+      - name: Store benchmark result
+        uses: benchmark-action/github-action-benchmark@v1
+        with:
+          tool: 'julia'
+          output-file-path: benchmark/output.json
+          benchmark-data-dir-path: benchmark-action/dev/bench
+          gh-pages-branch: bench-pages
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          summary-always: true
+          # Show alert with commit comment on detecting possible performance regression
+          alert-threshold: '200%'
+          comment-on-alert: true
+          fail-on-alert: true