[ci] Enabling aws-linux-scale-rocm to 10%

.github/workflows/multi_arch_build_portable_linux.yml

@@ -42,6 +42,10 @@ on:
         type: string
         default: ""
         description: "Comma-separated build stages to skip (artifacts already copied by the orchestrator)"
+      build_runs_on:
+        type: string
+        default: "azure-linux-scale-rocm"
+        description: "Build runner label (selected by configure script with weighted distribution)"
       release_type:
         description: 'Release type: "" for CI, or "dev", "nightly", "prerelease".'
         type: string
@@ -74,6 +78,7 @@ jobs:
       dist_amdgpu_families: ${{ inputs.dist_amdgpu_families }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       build_variant_cmake_preset: ${{ inputs.build_variant_cmake_preset }}
+      build_runs_on: ${{ inputs.build_runs_on }}
       release_type: ${{ inputs.release_type }}
       repository: ${{ inputs.repository }}
       ref: ${{ inputs.ref }}
@@ -96,6 +101,7 @@ jobs:
       dist_amdgpu_families: ${{ inputs.dist_amdgpu_families }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       build_variant_cmake_preset: ${{ inputs.build_variant_cmake_preset }}
+      build_runs_on: ${{ inputs.build_runs_on }}
       release_type: ${{ inputs.release_type }}
       repository: ${{ inputs.repository }}
       ref: ${{ inputs.ref }}
@@ -128,6 +134,7 @@ jobs:
       dist_amdgpu_families: ${{ inputs.dist_amdgpu_families }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       build_variant_cmake_preset: ${{ inputs.build_variant_cmake_preset }}
+      build_runs_on: ${{ inputs.build_runs_on }}
       release_type: ${{ inputs.release_type }}
       repository: ${{ inputs.repository }}
       ref: ${{ inputs.ref }}
@@ -154,6 +161,7 @@ jobs:
       dist_amdgpu_families: ${{ inputs.dist_amdgpu_families }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       build_variant_cmake_preset: ${{ inputs.build_variant_cmake_preset }}
+      build_runs_on: ${{ inputs.build_runs_on }}
       release_type: ${{ inputs.release_type }}
       repository: ${{ inputs.repository }}
       ref: ${{ inputs.ref }}
@@ -176,6 +184,7 @@ jobs:
       dist_amdgpu_families: ${{ inputs.dist_amdgpu_families }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       build_variant_cmake_preset: ${{ inputs.build_variant_cmake_preset }}
+      build_runs_on: ${{ inputs.build_runs_on }}
       release_type: ${{ inputs.release_type }}
       repository: ${{ inputs.repository }}
       ref: ${{ inputs.ref }}
@@ -198,6 +207,7 @@ jobs:
       dist_amdgpu_families: ${{ inputs.dist_amdgpu_families }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       build_variant_cmake_preset: ${{ inputs.build_variant_cmake_preset }}
+      build_runs_on: ${{ inputs.build_runs_on }}
       release_type: ${{ inputs.release_type }}
       repository: ${{ inputs.repository }}
       ref: ${{ inputs.ref }}
@@ -220,6 +230,7 @@ jobs:
       dist_amdgpu_families: ${{ inputs.dist_amdgpu_families }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       build_variant_cmake_preset: ${{ inputs.build_variant_cmake_preset }}
+      build_runs_on: ${{ inputs.build_runs_on }}
       release_type: ${{ inputs.release_type }}
       repository: ${{ inputs.repository }}
       ref: ${{ inputs.ref }}
@@ -242,6 +253,7 @@ jobs:
       dist_amdgpu_families: ${{ inputs.dist_amdgpu_families }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       build_variant_cmake_preset: ${{ inputs.build_variant_cmake_preset }}
+      build_runs_on: ${{ inputs.build_runs_on }}
       release_type: ${{ inputs.release_type }}
       repository: ${{ inputs.repository }}
       ref: ${{ inputs.ref }}
@@ -271,6 +283,7 @@ jobs:
       dist_amdgpu_families: ${{ inputs.dist_amdgpu_families }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       build_variant_cmake_preset: ${{ inputs.build_variant_cmake_preset }}
+      build_runs_on: ${{ inputs.build_runs_on }}
       release_type: ${{ inputs.release_type }}
       repository: ${{ inputs.repository }}
       ref: ${{ inputs.ref }}
@@ -293,6 +306,7 @@ jobs:
       dist_amdgpu_families: ${{ inputs.dist_amdgpu_families }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       build_variant_cmake_preset: ${{ inputs.build_variant_cmake_preset }}
+      build_runs_on: ${{ inputs.build_runs_on }}
       release_type: ${{ inputs.release_type }}
       repository: ${{ inputs.repository }}
       ref: ${{ inputs.ref }}

.github/workflows/multi_arch_build_portable_linux_artifacts.yml

@@ -53,6 +53,10 @@ on:
         description: 'Release type: "" for CI, or "dev", "nightly", "prerelease". Controls artifact bucket and IAM role.'
         type: string
         default: ""
+      build_runs_on:
+        description: "Build runner label (selected by configure script with weighted distribution)"
+        type: string
+        default: "azure-linux-scale-rocm"
       repository:
         description: "Repository to checkout. Defaults to github.repository."
         type: string
@@ -65,7 +69,7 @@ on:
 jobs:
   build_stage:
     name: ${{ inputs.stage_display_name }}
-    runs-on: ${{ contains(inputs.build_variant_cmake_preset, 'san') && 'azure-linux-scale-rocm-heavy-ramdisk' || 'azure-linux-scale-rocm' }}
+    runs-on: ${{ inputs.build_runs_on }}
     timeout-minutes: ${{ inputs.timeout_minutes }}
     permissions:
       id-token: write

.github/workflows/multi_arch_build_windows.yml

@@ -38,6 +38,10 @@ on:
         type: string
         default: ""
         description: "Comma-separated build stages to skip (artifacts already copied by the orchestrator)"
+      build_runs_on:
+        type: string
+        default: ""
+        description: "Build runner label (not currently used for Windows, reserved for future use)"
       rocm_package_version:
         type: string
       release_type:

.github/workflows/multi_arch_ci_linux.yml

@@ -78,6 +78,7 @@ jobs:
       build_variant_suffix: ${{ fromJSON(inputs.build_config).build_variant_suffix }}
       expect_failure: ${{ fromJSON(inputs.build_config).expect_failure }}
       prebuilt_stages: ${{ fromJSON(inputs.build_config).prebuilt_stages }}
+      build_runs_on: ${{ fromJSON(inputs.build_config).build_runs_on }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       release_type: ${{ inputs.release_type }}
     permissions:

.github/workflows/multi_arch_ci_windows.yml

@@ -83,6 +83,7 @@ jobs:
       build_variant_suffix: ${{ fromJSON(inputs.build_config).build_variant_suffix }}
       expect_failure: ${{ fromJSON(inputs.build_config).expect_failure }}
       prebuilt_stages: ${{ fromJSON(inputs.build_config).prebuilt_stages }}
+      build_runs_on: ${{ fromJSON(inputs.build_config).build_runs_on }}
       rocm_package_version: ${{ inputs.rocm_package_version }}
       release_type: ${{ inputs.release_type }}
     permissions:

build_tools/github_actions/amdgpu_family_matrix.py

@@ -45,6 +45,47 @@ def select_weighted_label(labels_config: list[dict], context_name: str) -> str:
     return selected["label"]
 
 
+# Build runner configuration for Linux builds
+# Uses weighted distribution: 90% Azure, 10% AWS
+# Sanitizer builds (asan/tsan) use ramdisk variants (100% Azure, no AWS yet)
+BUILD_RUNNER_LABELS = {
+    "linux": {
+        "default": [
+            {"label": "azure-linux-scale-rocm", "weight": 0.90},
+            {"label": "aws-linux-scale-rocm", "weight": 0.10},
+        ],
+        "sanitizer": [
+            {"label": "azure-linux-scale-rocm-heavy-ramdisk", "weight": 1.0},
+        ],
+    },
+    "windows": {
+        "default": [
+            {"label": "azure-windows-scale-rocm", "weight": 1.0},
+        ],
+    },
+}
+
+
+def select_build_runner(platform: str, build_variant: str) -> str:
+    """Select a build runner label based on platform and build variant."""
+    if platform not in BUILD_RUNNER_LABELS:
+        # Platform not configured for weighted selection, return default
+        print(f"  No build runner config for platform {platform}, using default")
+        return ""
+
+    platform_config = BUILD_RUNNER_LABELS[platform]
+
+    # Use sanitizer runners for asan/tsan builds
+    if "san" in build_variant:
+        labels_config = platform_config.get("sanitizer", platform_config["default"])
+        context_name = f"build-runner ({platform}, {build_variant})"
+    else:
+        labels_config = platform_config["default"]
+        context_name = f"build-runner ({platform})"
+
+    return select_weighted_label(labels_config, context_name)
+
+
 all_build_variants = {
     "linux": {
         "release": {

build_tools/github_actions/configure_ci.py

@@ -57,6 +57,7 @@
 from amdgpu_family_matrix import (
     all_build_variants,
     get_all_families_for_trigger_types,
+    select_build_runner,
     select_weighted_label,
 )
 from fetch_test_configurations import test_matrix, functional_matrix
@@ -453,6 +454,12 @@ def matrix_generator(
                 ):
                     matrix_row["test-runs-on"] = matrix_row["test-runs-on-sandbox"]
 
+                # Select build runner using weighted distribution (90% Azure, 10% AWS)
+                # Sanitizer builds use ramdisk variants
+                matrix_row["build-runs-on"] = select_build_runner(
+                    platform, base_args.get("build_variant", "release")
+                )
+
                 matrix_output.append(matrix_row)
 
     print(f"Generated build matrix: {str(matrix_output)}")

build_tools/github_actions/configure_multi_arch_ci.py

@@ -58,6 +58,7 @@
 from amdgpu_family_matrix import (
     all_build_variants,
     get_all_families_for_trigger_types,
+    select_build_runner,
     select_weighted_label,
 )
 from configure_ci_path_filters import (
@@ -417,6 +418,8 @@ class BuildConfig:
     build_variant_cmake_preset: str
     expect_failure: bool
     build_pytorch: bool
+    # Build runner label for this platform/variant combination
+    build_runs_on: str = ""
     # Prebuilt stage configuration — set by configure() from JobDecisions.
     prebuilt_stages: list[str] = field(default_factory=list)
     baseline_run_id: str = ""
@@ -885,6 +888,9 @@ def _expand_build_config_for_platform(
     expect_pytorch_failure = variant_config.get("expect_pytorch_failure", False)
     suffix = variant_config.get("build_variant_suffix", "")
 
+    # Select build runner using weighted distribution
+    build_runs_on = select_build_runner(platform, ci_inputs.build_variant)
+
     return BuildConfig(
         per_family_info=per_family_info,
         dist_amdgpu_families=";".join(family_names),
@@ -894,6 +900,7 @@ def _expand_build_config_for_platform(
         build_variant_cmake_preset=variant_config["build_variant_cmake_preset"],
         expect_failure=expect_failure,
         build_pytorch=not expect_failure and not expect_pytorch_failure,
+        build_runs_on=build_runs_on,
         prebuilt_stages=prebuilt_stages or [],
         baseline_run_id=baseline_run_id,
     )

build_tools/github_actions/tests/configure_multi_arch_ci_test.py

@@ -1134,5 +1134,50 @@ def test_families_without_multi_label_use_primary_only(self):
                 self.assertEqual(gfx103x_info["test-runs-on"], "linux-gfx1030-gpu-rocm")
 
 
+# ---------------------------------------------------------------------------
+# Build runner selection
+# ---------------------------------------------------------------------------
+
+
+class TestBuildRunnerSelection(unittest.TestCase):
+    """Test weighted random selection of build runners (Azure vs AWS)."""
+
+    def test_select_build_runner_weighted_selection(self):
+        """Test weighted selection: Azure (90%) vs AWS (10%) for default builds."""
+        from amdgpu_family_matrix import select_build_runner
+
+        # Random < 0.9 should select Azure
+        with patch("random.random", return_value=0.5):
+            self.assertEqual(
+                select_build_runner("linux", "release"), "azure-linux-scale-rocm"
+            )
+
+        # Random >= 0.9 should select AWS
+        with patch("random.random", return_value=0.95):
+            self.assertEqual(
+                select_build_runner("linux", "release"), "aws-linux-scale-rocm"
+            )
+
+        # Random >= 0.9 should select AWS
+        with patch("random.random", return_value=0.95):
+            self.assertEqual(
+                select_build_runner("windows", "release"), "azure-windows-scale-rocm"
+            )
+
+    def test_select_build_runner_sanitizer_uses_ramdisk(self):
+        """Sanitizer builds (asan/tsan) should always use Azure ramdisk runner."""
+        from amdgpu_family_matrix import select_build_runner
+
+        with patch("random.random", return_value=0.99):
+            self.assertEqual(
+                select_build_runner("linux", "asan"),
+                "azure-linux-scale-rocm-heavy-ramdisk",
+            )
+            self.assertEqual(
+                select_build_runner("linux", "tsan"),
+                "azure-linux-scale-rocm-heavy-ramdisk",
+            )
+
+
 if __name__ == "__main__":
     unittest.main()