e.g. https://webkit-queues.webkit.org/results/9366267 RuntimeError raised: Timed out while waiting for data migration 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 246, in run if not self._set_up_run(tests_to_run): File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/layout_tests/controllers/manager.py", line 181, in _set_up_run self._port.setup_test_run(self._options.device_class) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/port/ios.py", line 160, in setup_test_run self._create_devices(device_class) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/port/ios_simulator.py", line 103, in _create_devices SimulatedDeviceManager.initialize_devices([request] * self.child_processes(), self.host) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/xcode/simulated_device.py", line 368, in initialize_devices SimulatedDeviceManager.wait_until_data_migration_is_done(host, max(0, deadline - time.time())) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/xcode/simulated_device.py", line 428, in wait_until_data_migration_is_done raise RuntimeError('Timed out while waiting for data migration') RuntimeError: Timed out while waiting for data migration Error in atexit._run_exitfuncs: Traceback (most recent call last): File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/atexit.py", line 24, in _run_exitfuncs func(*targs, **kargs) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/xcode/simulated_device.py", line 446, in tear_down device.platform_device._tear_down(deadline - time.time()) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/xcode/simulated_device.py", line 522, in _tear_down self._shut_down(deadline - time.time()) File "/Volumes/Data/EWS/WebKit/Tools/Scripts/webkitpy/xcode/simulated_device.py", line 508, in _shut_down raise RuntimeError('Timed out while waiting for {} to shut down'.format(self.udid)) RuntimeError: Timed out while waiting for 3FDF5418-1774-4710-B947-9952835E2563 to shut down - R. Niwa