Split into two workflows

One workflow generates the report and publishes it on commits to main. The other attempts only to comment on PRs.

.github/workflows/benchmark-go-main.yml

@@ -0,0 +1,38 @@
+name: Benchmark Go
+
+on:
+  push:
+    branches:
+      - main
+
+permissions:
+  # deployments permission to deploy GitHub pages website
+  deployments: write
+  # contents permission to update benchmark contents in gh-pages branch
+  contents: write
+
+jobs:
+  benchmark:
+    name: Performance regression check
+    runs-on: ubuntu-latest
+    steps:
+      - name: Fetch Repo
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+      - name: Install Go
+        uses: actions/setup-go@3041bf56c941b39c61721a86cd11f3bb1338122a # v5.1.0
+        with:
+          go-version-file: go.mod
+
+      - name: Run benchmark
+        run: set -o pipefail; go test ./... -benchmem -run=^$ -bench . | tee output.txt
+
+      - name: Store benchmark result
+        uses: benchmark-action/github-action-benchmark@d48d326b4ca9ba73ca0cd0d59f108f9e02a381c7 # v1.20.4
+        with:
+          tool: 'go'
+          output-file-path: output.txt
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          auto-push: true
+          alert-threshold: "150%"
+          fail-on-alert: true

.github/workflows/benchmark-go.yml → .github/workflows/benchmark-go-pr.yml

@@ -1,18 +1,11 @@
 name: Benchmark Go
 
 on:
-  push:
-    branches:
-      - main
   pull_request:
     branches:
       - main
 
 permissions:
-  # deployments permission to deploy GitHub pages website
-  deployments: write
-  # contents permission to update benchmark contents in gh-pages branch
-  contents: write
   # allow posting comments to pull request
   pull-requests: write
 
@@ -38,7 +31,6 @@ jobs:
           tool: 'go'
           output-file-path: output.txt
           github-token: ${{ secrets.GITHUB_TOKEN }}
-          auto-push: true
           alert-threshold: "150%"
           fail-on-alert: true
           comment-on-alert: true # notify on PR if alert triggers