[CI] add Precision Regression Test on Nightly Run CI (#26902)

.github/workflows/nightly-test-nvidia.yml

@@ -27,6 +27,7 @@ on:
           - 'nightly-test-kernel-1-gpu-h100'
           - 'nightly-test-diffusion-comparison'
           - 'nightly-test-kernel-8-gpu-h200'
+          - 'nightly-test-precision-8-gpu-h200'
   workflow_call:
     inputs:
       ref:
@@ -604,6 +605,39 @@ jobs:
       - uses: ./.github/actions/upload-cuda-coredumps
         if: failure()
 
+  # Nightly precision regression - per-layer hidden state comparison
+  nightly-test-precision-8-gpu-h200:
+    if: github.repository == 'sgl-project/sglang' && (inputs.job_filter == '' || inputs.job_filter == 'all' || inputs.job_filter == 'nightly-test-precision-8-gpu-h200')
+    runs-on: 8-gpu-h200
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.ref || github.ref }}
+
+      - uses: ./.github/actions/check-maintenance
+
+      - name: Install dependencies
+        run: |
+          bash scripts/ci/cuda/ci_install_dependency.sh
+
+      - name: Run precision regression test
+        timeout-minutes: 120
+        env:
+          SGLANG_PRECISION_BASELINE_DIR: /tmp/sglang_precision_baselines
+          # Required: the test errors if SGLANG_PRECISION_HF_REPO is unset (no
+          # local-only mode). Set the var + the HF_TOKEN_PRECISION_STORE secret.
+          SGLANG_PRECISION_HF_REPO: ${{ vars.SGLANG_PRECISION_HF_REPO }}
+          SGLANG_PRECISION_HF_REVISION: ${{ vars.SGLANG_PRECISION_HF_REVISION || 'main' }}
+          HF_TOKEN: ${{ secrets.HF_TOKEN_PRECISION_STORE }}
+          SGLANG_PRECISION_COMMIT: ${{ github.sha }}
+        run: |
+          cd test
+          python3 run_suite.py --hw cuda --suite nightly-precision-8-gpu-h200 --nightly --continue-on-error --timeout-per-file 3600
+
+      - uses: ./.github/actions/upload-cuda-coredumps
+        if: failure()
+
   # Consolidate performance metrics from all jobs
   consolidate-metrics:
     if: github.repository == 'sgl-project/sglang' && always()
@@ -662,6 +696,7 @@ jobs:
       - nightly-test-perf-4-gpu-b200
       - nightly-test-specialized-8-gpu-b200
       - nightly-test-diffusion-comparison
+      - nightly-test-precision-8-gpu-h200
       - consolidate-metrics
     runs-on: ubuntu-latest
     steps: