C1 Phase-1 baseline — land tier3_baseline.json on main (blocks gate #1; royal-tern-883 stood down 2026-05-11 awaiting this)

.github/workflows/tier3-baseline-capture.yml

@@ -0,0 +1,99 @@
+# Manual C1 Phase-1 Tier-3 mirror baseline capture (``tier3_baseline.json``).
+#
+# Dispatched on `ubicloud-standard-2` (R-3 per ``docs/audit/c1-r3-canonical-bench-host-decision-matrix.md``).
+# Runs five independent bench jobs (separate VMs), aggregates per procedure §2 / R-7 via
+# ``scripts/aggregate_tier3_baseline.py``.
+#
+# **Phase-1 gate (R-7):** the canonical baseline lives in the repo tree at
+# ``src/v3/compiler/benches/tier3_baseline.json`` (merged on ``main`` before mirror dissolution PRs).
+# This workflow does **not** replace that file: it is a **recapture / audit** path for
+# Director-approved baseline refresh or for comparing fresh Criterion output against the
+# committed baseline (diff the artifact vs the checked-in JSON; land updates only via normal PR).
+#
+# Once this YAML exists on ``main``, operators may ``gh workflow run tier3-baseline-capture.yml``,
+# then review or diff the emitted ``tier3_baseline.json`` artifact.
+
+name: Tier-3 baseline capture
+
+on:
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: tier3-baseline-capture-${{ github.repository }}
+  cancel-in-progress: false
+
+jobs:
+  capture-run:
+    strategy:
+      fail-fast: false
+      matrix:
+        run_number: [1, 2, 3, 4, 5]
+    runs-on: ubicloud-standard-2
+    timeout-minutes: 60
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Rust
+        uses: actions-rust-lang/setup-rust-toolchain@v1.16.0
+        with:
+          cache: true
+          rustflags: ""
+
+      - name: Run tier3 mirror benchmarks
+        run: cargo bench --bench tier3_mirror_perf -p v3-compiler
+
+      - name: Stage capture bundle (criterion + rustc provenance)
+        run: |
+          mkdir -p staging
+          cp -a target/criterion staging/criterion
+          rustc --version | tee staging/rustc_version.txt
+
+      - name: Upload capture bundle
+        uses: actions/upload-artifact@v4
+        with:
+          name: tier3-criterion-${{ matrix.run_number }}
+          path: staging
+
+  aggregate:
+    needs: capture-run
+    runs-on: ubicloud-standard-2
+    timeout-minutes: 15
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Download criterion artifacts
+        uses: actions/download-artifact@v4
+        with:
+          pattern: tier3-criterion-*
+          path: runs
+          merge-multiple: false
+
+      - name: Aggregate into tier3_baseline.json
+        run: |
+          set -euxo pipefail
+          # Artifact-only aggregate (compare vs src/v3/compiler/benches/tier3_baseline.json in-tree).
+          # Each matrix job uploaded `staging/` with `criterion/` + rustc_version.txt
+          shopt -s nullglob
+          bundles=(runs/tier3-criterion-*)
+          if [ "${#bundles[@]}" -lt 3 ]; then
+            echo "::error::expected ≥3 capture bundles under runs/tier3-criterion-*, got ${#bundles[@]}"
+            ls -la runs || true
+            exit 1
+          fi
+          mapfile -t sorted < <(printf '%s\n' "${bundles[@]}" | sort -V)
+          python3 scripts/aggregate_tier3_baseline.py \
+            --host-id ubicloud-standard-2 \
+            --git-sha "${GITHUB_SHA}" \
+            --output tier3_baseline.json \
+            "${sorted[@]}"
+
+      - name: Upload baseline JSON
+        uses: actions/upload-artifact@v4
+        with:
+          name: tier3-baseline-json
+          path: tier3_baseline.json