diff --git a/.github/workflows/nightly-test-nvidia.yml b/.github/workflows/nightly-test-nvidia.yml
index 064a7b2ed..dc9ac1f2b 100644
--- a/.github/workflows/nightly-test-nvidia.yml
+++ b/.github/workflows/nightly-test-nvidia.yml
@@ -24,7 +24,7 @@ on:
           - 'nightly-test-perf-4-gpu-b200'
           - 'nightly-test-perf-8-gpu-b200'
           - 'nightly-test-specialized-8-gpu-b200'
-          - 'nightly-test-perf-4-gpu-gb300'
+#           - 'nightly-test-perf-4-gpu-gb300'  # temporarily disabled due to runner availability
           - 'nightly-test-kernel-1-gpu-h100'
           - 'nightly-test-diffusion'
           - 'nightly-test-kernel-8-gpu-h200'
@@ -544,68 +544,69 @@ jobs:
         if: failure()
 
   # GB300 (Grace-Blackwell NVL4) performance tests - 4 GPU (ARM64)
-  nightly-test-perf-4-gpu-gb300:
-    if: github.repository == 'sgl-project/sglang' && (inputs.job_filter == '' || inputs.job_filter == 'all' || inputs.job_filter == 'nightly-test-perf-4-gpu-gb300')
-    name: nightly-test-perf-4-gpu-gb300 (${{ matrix.model }})
-    runs-on: 4-gpu-gb300-nightly
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-          - model: glm5-nvfp4
-            suite: nightly-4-gpu-gb300-glm5-nvfp4
-          - model: qwen35-fp8
-            suite: nightly-4-gpu-gb300-qwen35-fp8
-          - model: deepseek-v4-pro-fp4
-            suite: nightly-4-gpu-gb300-deepseek-v4-pro-fp4
-          - model: kimi-k25-nvfp4
-            suite: nightly-4-gpu-gb300-kimi-k25-nvfp4
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v4
-        with:
-          ref: ${{ inputs.ref || github.ref }}
-
-      - uses: ./.github/actions/check-maintenance
-
-      - name: Install dependencies
-        env:
-          GRACE_BLACKWELL: "1"
-        run: |
-          bash scripts/ci/cuda/ci_install_deepep.sh
-
-      - name: Run test
-        timeout-minutes: 600
-        env:
-          TRACE_BASE_URL: https://raw.githubusercontent.com/sglang-bot/sglang-ci-data/main/traces/${{ github.run_id }}
-          PERFETTO_RELAY_URL: ${{ vars.PERFETTO_RELAY_URL }}
-          GPU_CONFIG: "4-gpu-gb300"
-        run: |
-          cd test
-          python3 run_suite.py --hw cuda --suite ${{ matrix.suite }} --nightly --continue-on-error --timeout-per-file 7200
-
-      - name: Publish traces to storage repo
-        if: always()
-        continue-on-error: true
-        env:
-          GITHUB_TOKEN: ${{ secrets.GH_PAT_FOR_NIGHTLY_CI_DATA }}
-          GITHUB_RUN_ID: ${{ github.run_id }}
-          GITHUB_RUN_NUMBER: ${{ github.run_number }}
-        run: |
-          TRACE_ARGS=""
-          for dir in test/performance_profiles_*/; do
-            [ -d "$dir" ] && TRACE_ARGS="$TRACE_ARGS --traces-dir $dir"
-          done
-          if [ -n "$TRACE_ARGS" ]; then
-            python3 scripts/ci/utils/publish_traces.py $TRACE_ARGS
-            find test/performance_profiles_*/ -name '*.json.gz' -delete
-          else
-            echo "No trace directories found, skipping publish"
-          fi
-
-      - uses: ./.github/actions/upload-cuda-coredumps
-        if: failure()
-
+  # temporarily disabled due to runner availability
+#   nightly-test-perf-4-gpu-gb300:
+#     if: github.repository == 'sgl-project/sglang' && (inputs.job_filter == '' || inputs.job_filter == 'all' || inputs.job_filter == 'nightly-test-perf-4-gpu-gb300')
+#     name: nightly-test-perf-4-gpu-gb300 (${{ matrix.model }})
+#     runs-on: 4-gpu-gb300-nightly
+#     strategy:
+#       fail-fast: false
+#       matrix:
+#         include:
+#           - model: glm5-nvfp4
+#             suite: nightly-4-gpu-gb300-glm5-nvfp4
+#           - model: qwen35-fp8
+#             suite: nightly-4-gpu-gb300-qwen35-fp8
+#           - model: deepseek-v4-pro-fp4
+#             suite: nightly-4-gpu-gb300-deepseek-v4-pro-fp4
+#           - model: kimi-k25-nvfp4
+#             suite: nightly-4-gpu-gb300-kimi-k25-nvfp4
+#     steps:
+#       - name: Checkout code
+#         uses: actions/checkout@v4
+#         with:
+#           ref: ${{ inputs.ref || github.ref }}
+#
+#       - uses: ./.github/actions/check-maintenance
+#
+#       - name: Install dependencies
+#         env:
+#           GRACE_BLACKWELL: "1"
+#         run: |
+#           bash scripts/ci/cuda/ci_install_deepep.sh
+#
+#       - name: Run test
+#         timeout-minutes: 600
+#         env:
+#           TRACE_BASE_URL: https://raw.githubusercontent.com/sglang-bot/sglang-ci-data/main/traces/${{ github.run_id }}
+#           PERFETTO_RELAY_URL: ${{ vars.PERFETTO_RELAY_URL }}
+#           GPU_CONFIG: "4-gpu-gb300"
+#         run: |
+#           cd test
+#           python3 run_suite.py --hw cuda --suite ${{ matrix.suite }} --nightly --continue-on-error --timeout-per-file 7200
+#
+#       - name: Publish traces to storage repo
+#         if: always()
+#         continue-on-error: true
+#         env:
+#           GITHUB_TOKEN: ${{ secrets.GH_PAT_FOR_NIGHTLY_CI_DATA }}
+#           GITHUB_RUN_ID: ${{ github.run_id }}
+#           GITHUB_RUN_NUMBER: ${{ github.run_number }}
+#         run: |
+#           TRACE_ARGS=""
+#           for dir in test/performance_profiles_*/; do
+#             [ -d "$dir" ] && TRACE_ARGS="$TRACE_ARGS --traces-dir $dir"
+#           done
+#           if [ -n "$TRACE_ARGS" ]; then
+#             python3 scripts/ci/utils/publish_traces.py $TRACE_ARGS
+#             find test/performance_profiles_*/ -name '*.json.gz' -delete
+#           else
+#             echo "No trace directories found, skipping publish"
+#           fi
+#
+#       - uses: ./.github/actions/upload-cuda-coredumps
+#         if: failure()
+#
   # Specialized B200 tests - 8 GPU, for specific backends and configs
   nightly-test-specialized-8-gpu-b200:
     if: github.repository == 'sgl-project/sglang' && (inputs.job_filter == '' || inputs.job_filter == 'all' || inputs.job_filter == 'nightly-test-perf-8-gpu-b200' || inputs.job_filter == 'nightly-test-specialized-8-gpu-b200')
@@ -791,7 +792,7 @@ jobs:
       - nightly-test-vlm-perf-2-gpu-h100
       - nightly-test-perf-4-gpu-b200
       - nightly-test-specialized-8-gpu-b200
-      - nightly-test-perf-4-gpu-gb300
+#       - nightly-test-perf-4-gpu-gb300  # temporarily disabled due to runner availability
       - nightly-test-diffusion
       - nightly-test-precision-8-gpu-h200
       - consolidate-metrics
diff --git a/.github/workflows/pr-test.yml b/.github/workflows/pr-test.yml
index d7261d566..e7ff56f62 100644
--- a/.github/workflows/pr-test.yml
+++ b/.github/workflows/pr-test.yml
@@ -520,19 +520,20 @@ jobs:
       timeout_per_file: '1800'
     secrets: inherit
 
-  base-c-test-4-gpu-gb300:
-    needs: [check-changes, call-gate, wait-for-base-b, sgl-kernel-build-wheels]
-    if: ${{ !failure() && !cancelled() }}
-    uses: ./.github/workflows/_pr-test-stage.yml
-    with:
-      self_name: base-c-test-4-gpu-gb300
-      runner_config: 4-gpu-gb300
-      check_changes: ${{ toJson(needs.check-changes.outputs) }}
-      caller_inputs: ${{ toJson(inputs) }}
-      partitions: ${{ needs.check-changes.outputs.partitions }}
-      run_timeout_minutes: '30'
-      timeout_per_file: '1800'
-    secrets: inherit
+  # temporarily disabled due to runner availability
+#   base-c-test-4-gpu-gb300:
+#     needs: [check-changes, call-gate, wait-for-base-b, sgl-kernel-build-wheels]
+#     if: ${{ !failure() && !cancelled() }}
+#     uses: ./.github/workflows/_pr-test-stage.yml
+#     with:
+#       self_name: base-c-test-4-gpu-gb300
+#       runner_config: 4-gpu-gb300
+#       check_changes: ${{ toJson(needs.check-changes.outputs) }}
+#       caller_inputs: ${{ toJson(inputs) }}
+#       partitions: ${{ needs.check-changes.outputs.partitions }}
+#       run_timeout_minutes: '30'
+#       timeout_per_file: '1800'
+#     secrets: inherit
 
   pr-test-finish:
     needs:
@@ -564,7 +565,7 @@ jobs:
         base-c-test-deepep-4-gpu-b200,
         base-c-test-deepep-8-gpu-h200,
         base-c-test-4-gpu-b200,
-        base-c-test-4-gpu-gb300,
+#         base-c-test-4-gpu-gb300,  # temporarily disabled due to runner availability
       ]
     if: always()
     runs-on: ubuntu-latest
diff --git a/.github/workflows/release-whl-deepgemm.yml b/.github/workflows/release-whl-deepgemm.yml
index c0bddc930..6ce930240 100644
--- a/.github/workflows/release-whl-deepgemm.yml
+++ b/.github/workflows/release-whl-deepgemm.yml
@@ -238,9 +238,10 @@ jobs:
           - arch_label: sm100
             runner: 8-gpu-b200
             wheel_arch: x86_64
-          - arch_label: sm100-aarch64
-            runner: 4-gpu-gb300
-            wheel_arch: aarch64
+          # temporarily disabled due to runner availability
+#           - arch_label: sm100-aarch64
+#             runner: 4-gpu-gb300
+#             wheel_arch: aarch64
     runs-on: ${{ matrix.runner }}
     timeout-minutes: 120
     steps: