Parallelize system tests per tutorial

.github/workflows/system-tests-manual.yml

@@ -8,6 +8,10 @@ on:
         default: 'release'
         required: true
         type: string
+      parallel:
+        description: 'Split into per-tutorial parallel jobs'
+        default: false
+        type: boolean
       system_tests_branch:
         description: 'Use the system tests from'
         default: 'develop'
@@ -53,11 +57,42 @@ on:
         type: string
 
 jobs:
+  prepare-matrix:
+    name: Prepare test matrix
+    runs-on: ubuntu-latest
+    outputs:
+      matrix: ${{ steps.matrix.outputs.matrix }}
+    steps:
+      - name: Check out tutorials
+        uses: actions/checkout@v7
+        with:
+          ref: ${{ inputs.system_tests_branch }}
+      - name: Install Python dependencies
+        run: pip install --user -r tests/requirements.txt
+      - name: Build matrix from selected suites
+        id: matrix
+        working-directory: tests
+        env:
+          SUITES: ${{ inputs.suites }}
+          PARALLEL: ${{ inputs.parallel }}
+        run: |
+          MODE=serial
+          if [ "$PARALLEL" = "true" ]; then
+            MODE=parallel
+          fi
+          python3 prepare_matrix.py --suites "$SUITES" --mode "$MODE" --format=github > matrix.json
+          echo "matrix=$(cat matrix.json)" >> "$GITHUB_OUTPUT"
+
   run-system-tests:
-    name: Trigger system tests
+    name: ${{ matrix.tutorial != '' && format('Trigger system tests ({0})', matrix.tutorial) || 'Trigger system tests' }}
+    needs: prepare-matrix
+    strategy:
+      fail-fast: false
+      matrix:
+        include: ${{ fromJson(needs.prepare-matrix.outputs.matrix) }}
     uses: $/.github/workflows/system-tests.yml
     with:
-      suites: ${{ inputs.suites || 'release' }}
+      suites: ${{ matrix.suites }}
       build_args: "TUTORIALS_REF:${{ inputs.ref-tutorials }},\
         PRECICE_REF:${{ inputs.ref-precice }},\
         PYTHON_BINDINGS_REF:${{ inputs.ref-python-bindings }},\
@@ -73,3 +108,4 @@ jobs:
         SU2_ADAPTER_REF:${{ inputs.ref-su2-adapter }}"
       system_tests_branch: ${{ inputs.system_tests_branch || 'develop' }}
       log_level: "INFO"
+      job_label: ${{ matrix.tutorial }}

.github/workflows/system-tests-nightly.yml

@@ -6,8 +6,33 @@ on:
       timezone: "Europe/Berlin"
 
 jobs:
+  prepare-matrix:
+    name: Prepare test matrix
+    runs-on: ubuntu-latest
+    outputs:
+      matrix: ${{ steps.matrix.outputs.matrix }}
+    steps:
+      - name: Check out tutorials
+        uses: actions/checkout@v7
+        with:
+          ref: develop
+      - name: Install Python dependencies
+        run: pip install --user -r tests/requirements.txt
+      - name: Build serial matrix for release
+        id: matrix
+        working-directory: tests
+        run: |
+          python3 prepare_matrix.py --suites release --mode serial --format=github > matrix.json
+          echo "matrix=$(cat matrix.json)" >> "$GITHUB_OUTPUT"
+
   run-system-tests:
     name: Trigger system tests
+    needs: prepare-matrix
+    strategy:
+      fail-fast: false
+      matrix:
+        include: ${{ fromJson(needs.prepare-matrix.outputs.matrix) }}
     uses: $/.github/workflows/system-tests.yml
     with:
-      suites: 'release'
+      suites: ${{ matrix.suites }}
+      job_label: ${{ matrix.tutorial }}

.github/workflows/system-tests.yml

@@ -21,8 +21,13 @@ on:
           description: 'TRUE or FALSE (FALSE -> Upload only when the workflow fails)'
           default: 'TRUE'
           type: string
+      job_label:
+        description: 'Optional label for job and artifact names (e.g. tutorial name)'
+        default: ''
+        type: string
 jobs:
   run_system_tests:
+    name: ${{ inputs.job_label != '' && format('System tests ({0})', inputs.job_label) || 'System tests' }}
     runs-on: [self-hosted, linux, x64, precice-tests-vm]
     steps:
     - name: Display a quick job summary
@@ -90,7 +95,7 @@ jobs:
       id: archive-logs
       uses: actions/upload-artifact@v7
       with:
-        name: system_tests_run_${{ github.run_id }}_${{ github.run_attempt }}_logs
+        name: system_tests_run_${{ github.run_id }}_${{ github.run_attempt }}${{ inputs.job_label != '' && format('_{0}', inputs.job_label) || '' }}_logs
         path: |
           runs/*/system-tests-build.log
           runs/*/system-tests-run.log
@@ -103,7 +108,7 @@ jobs:
       id: archive-diffs
       uses: actions/upload-artifact@v7
       with:
-        name: system_tests_run_${{ github.run_id }}_${{ github.run_attempt }}_diffs
+        name: system_tests_run_${{ github.run_id }}_${{ github.run_attempt }}${{ inputs.job_label != '' && format('_{0}', inputs.job_label) || '' }}_diffs
         path: |
           runs/*/diff-results/visualizations/**/*.png
         if-no-files-found: ignore
@@ -121,7 +126,7 @@ jobs:
       if: ${{ failure() || inputs.upload_artifacts == 'TRUE' }}
       uses: actions/upload-artifact@v7
       with:
-        name: system_tests_run_${{ github.run_id }}_${{ github.run_attempt }}_full
+        name: system_tests_run_${{ github.run_id }}_${{ github.run_attempt }}${{ inputs.job_label != '' && format('_{0}', inputs.job_label) || '' }}_full
         path: |
           runs/*
           !runs/tests/thirdparty

changelog-entries/789.md

@@ -0,0 +1 @@
+- Parallelize scheduled and manual `release` system tests via a per-tutorial GitHub Actions matrix derived from `tests.yaml` [#789](https://github.com/precice/tutorials/issues/789)

tests/README.md

@@ -34,6 +34,8 @@ The `Use workflow from` is a default option of GitHub Actions that concerns the
 
 The [System tests (nightly)](https://github.com/precice/tutorials/actions/workflows/system-tests-nightly.yml) executes the `release` test suite every night. The [System tests (weekly)](https://github.com/precice/tutorials/actions/workflows/system-tests-weekly.yml) executes the `extra` test suite once per week.
 
+The manual and nightly workflows always run a `prepare-matrix` job first. By default, suites run in a single serial matrix job. Enable the `parallel` input to split expandable suites (such as `release`) into one job per tutorial. If a parallel matrix job fails, re-run only that tutorial job from the Actions run page.
+
 ### Running from a pull request
 
 Several repositories include a workflow that allows triggering the system tests by adding the `trigger-system-tests` label to the pull request. The event is triggered only at the moment of adding the label, so you need to remove the label and add it again if needed.
@@ -83,10 +85,11 @@ This will build and connect Docker containers and run tutorials in the `runs/` d
 
 To clean up at the end, you might want to run a `docker system prune -a` and remove the `runs/` directory to save space.
 
-There are also some auxiliary scripts (run without arguments):
+There are also some auxiliary scripts:
 
-- `print_test_suites.py`: Print all test suites defined in `tests.yaml`
-- `print_case_combinations.py`: Print all possible combinations of participants in a tutorial, using its `metadata.yaml`.
+- `print_test_suites.py`: Print all test suites defined in `tests.yaml`. No arguments are expected.
+- `print_case_combinations.py`: Print all possible combinations of participants in a tutorial, using its `metadata.yaml`. No arguments are expected.
+- `prepare_matrix.py`: Preview how the manual and nightly workflows split selected suites into GitHub Actions matrix jobs. Run it as `python prepare_matrix.py --suites release --mode [serial|parallel] --format [pretty|github]`.
 
 ## Understanding the logs