e.g. https://webkit-queues.webkit.org/results/10084446 RuntimeError raised: Timed out while waiting for F856DA6C-99A9-4F53-A577-FF6214181E63 to shut down Traceback (most recent call last): File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/layout_tests/run_webkit_tests.py", line 85, in main run_details = run(port, options, args, stderr) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/layout_tests/run_webkit_tests.py", line 448, in run run_details = manager.run(args) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/layout_tests/controllers/manager.py", line 249, in run initial_results, retry_results, enabled_pixel_tests_in_retry = self._run_test_subset(default_device_tests, tests_to_skip) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/layout_tests/controllers/manager.py", line 293, in _run_test_subset self._clean_up_run() File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/layout_tests/controllers/manager.py", line 342, in _clean_up_run self._port.clean_up_test_run() File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/port/ios_simulator.py", line 103, in clean_up_test_run SimulatedDeviceManager.tear_down(self.host) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/xcode/simulated_device.py", line 444, in tear_down device.platform_device._tear_down(deadline - time.time()) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/xcode/simulated_device.py", line 538, in _tear_down self._shut_down(deadline - time.time()) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/xcode/simulated_device.py", line 524, in _shut_down raise RuntimeError('Timed out while waiting for {} to shut down'.format(self.udid)) RuntimeError: Timed out while waiting for F856DA6C-99A9-4F53-A577-FF6214181E63 to shut down Stopping HTTP server ... Stopping WebSocket server ... Stopping Web Platform Test server ... - R. Niwa