ci: Disable PerfPowerServices process on macos-15-intel (#2641)

* Disable the PerfPowerServices process on macos-15-intel runners to
  address known macOS 15 bug that significantly slows down the runner.
   - c.f. actions/runner-images#13358

Author: matthewfeickert

.github/workflows/ci.yml

@@ -39,6 +39,13 @@ jobs:
             python-version: '3.13'
 
     steps:
+    # c.f. https://github.com/actions/runner-images/issues/13358
+    - name: Work around x86 macOS bug for multiple CPU cores
+      if: matrix.os == 'macos-15-intel'
+      run: |
+        sudo defaults -currentHost write /Library/Preferences/com.apple.powerlogd SMCMonitorCadence 0
+        sudo killall PerfPowerServices || true
+
     - uses: actions/checkout@v6
 
     - name: Set up Python ${{ matrix.python-version }}

.github/workflows/dependencies-head.yml

@@ -24,6 +24,13 @@ jobs:
         python-version: ['3.13']
 
     steps:
+    # c.f. https://github.com/actions/runner-images/issues/13358
+    - name: Work around x86 macOS bug for multiple CPU cores
+      if: matrix.os == 'macos-15-intel'
+      run: |
+        sudo defaults -currentHost write /Library/Preferences/com.apple.powerlogd SMCMonitorCadence 0
+        sudo killall PerfPowerServices || true
+
     - uses: actions/checkout@v6
 
     - name: Set up Python ${{ matrix.python-version }}

.github/workflows/release_tests.yml

@@ -32,6 +32,13 @@ jobs:
       fail-fast: false
 
     steps:
+    # c.f. https://github.com/actions/runner-images/issues/13358
+    - name: Work around x86 macOS bug for multiple CPU cores
+      if: matrix.os == 'macos-15-intel'
+      run: |
+        sudo defaults -currentHost write /Library/Preferences/com.apple.powerlogd SMCMonitorCadence 0
+        sudo killall PerfPowerServices || true
+
     - uses: actions/checkout@v6
 
     - name: Set up Python ${{ matrix.python-version }}