x86- and amd64-generic-telemetry have been failing continuously since yesterday due to
core.about_tracing_integration_test.AboutTracingIntegrationTest.testBasicTraceRecording :

https://build.chromium.org/p/chromiumos.chromium/builders/x86-generic-telemetry/builds/10647
https://build.chromium.org/p/chromiumos.chromium/builders/amd64-generic-telemetry/builds/9899

From telemetry_UnitTests.perf.DEBUG log:

10/07 05:47:55.021 INFO |run_chromeos_tests:0052| [204/302] core.about_tracing_integration_test.AboutTracingIntegrationTest.testBasicTraceRecording queued
10/07 05:47:55.023 INFO |run_chromeos_tests:0052| [205/302] core.about_tracing_integration_test.AboutTracingIntegrationTest.testBasicTraceRecording failed unexpectedly 99.4423s:
10/07 05:47:55.024 INFO |run_chromeos_tests:0052|   Traceback (most recent call last):
10/07 05:47:55.024 INFO |run_chromeos_tests:0052|     File "/usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/testing/browser_test_case.py", line 41, in WrappedMethod
10/07 05:47:55.025 INFO |run_chromeos_tests:0052|       method(self)
10/07 05:47:55.026 INFO |run_chromeos_tests:0052|     File "/usr/local/telemetry/src/tools/perf/core/about_tracing_integration_test.py", line 36, in testBasicTraceRecording
10/07 05:47:55.027 INFO |run_chromeos_tests:0052|       action_runner.WaitForElement(selector='div[title~="Browser"]')
10/07 05:47:55.027 INFO |run_chromeos_tests:0052|     File "/usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/internal/actions/action_runner.py", line 239, in WaitForElement
10/07 05:47:55.028 INFO |run_chromeos_tests:0052|       timeout_in_seconds=timeout_in_seconds))
10/07 05:47:55.029 INFO |run_chromeos_tests:0052|     File "/usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/internal/actions/action_runner.py", line 48, in _RunAction
10/07 05:47:55.030 INFO |run_chromeos_tests:0052|       action.RunAction(self._tab)
10/07 05:47:55.030 INFO |run_chromeos_tests:0052|     File "/usr/local/telemetry/src/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 52, in traced_function
10/07 05:47:55.031 INFO |run_chromeos_tests:0052|       return func(*args, **kwargs)
10/07 05:47:55.032 INFO |run_chromeos_tests:0052|     File "/usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/internal/actions/wait.py", line 22, in RunAction
10/07 05:47:55.032 INFO |run_chromeos_tests:0052|       wait=True, timeout_in_seconds=self.timeout_in_seconds)
10/07 05:47:55.033 INFO |run_chromeos_tests:0052|     File "/usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/internal/actions/page_action.py", line 118, in EvaluateCallbackWithElement
10/07 05:47:55.034 INFO |run_chromeos_tests:0052|       tab.WaitForJavaScriptExpression(code, timeout_in_seconds)
10/07 05:47:55.034 INFO |run_chromeos_tests:0052|     File "/usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/internal/browser/web_contents.py", line 136, in WaitForJavaScriptExpression
10/07 05:47:55.035 INFO |run_chromeos_tests:0052|       e.message + '\n' + debug_message)
10/07 05:47:55.036 INFO |run_chromeos_tests:0052|   TimeoutException: Timed out while waiting 60s for IsJavaScriptExpressionTrue.
10/07 05:47:55.036 INFO |run_chromeos_tests:0052|   Console output:
10/07 05:47:55.037 INFO |run_chromeos_tests:0052|   (warning) chrome://tracing/tracing.js:2592: Unrecognized metadata name: IsTimeTicksHighResolution
10/07 05:47:55.038 INFO |run_chromeos_tests:0052|   (warning) chrome://tracing/tracing.js:2592: Malformed sched_wakeup event (<idle>-0     [003] dNs4  4111.796164: sched_wakeup: comm=rcu_sched pid=8 prio=120 target_cpu=003)
10/07 05:47:55.038 INFO |run_chromeos_tests:0052|   (error) chrome://tracing/tracing.js:2074: Error: The end timestamp of a thread running on CPU 2 is before its start timestamp.
10/07 05:47:55.039 INFO |run_chromeos_tests:0052|       at Cpu.closeActiveThread (chrome://tracing/tracing.js:2459:57)
10/07 05:47:55.040 INFO |run_chromeos_tests:0052|       at Cpu.switchActiveThread (chrome://tracing/tracing.js:2462:504)
10/07 05:47:55.040 INFO |run_chromeos_tests:0052|       at SchedParser.schedSwitchEvent (chrome://tracing/tracing.js:5514:71)
10/07 05:47:55.041 INFO |run_chromeos_tests:0052|       at FTraceImporter.<anonymous> (chrome://tracing/tracing.js:5599:33)
10/07 05:47:55.042 INFO |run_chromeos_tests:0052|       at FTraceImporter.forEachLine_ (chrome://tracing/tracing.js:5603:231)
10/07 05:47:55.042 INFO |run_chromeos_tests:0052|       at FTraceImporter.importCpuData_ (chrome://tracing/tracing.js:5598:123)
10/07 05:47:55.043 INFO |run_chromeos_tests:0052|       at FTraceImporter.importEvents (chrome://tracing/tracing.js:5567:498)
10/07 05:47:55.044 INFO |run_chromeos_tests:0052|       at Import.runImportEventsOnOneImporter (chrome://tracing/tracing.js:1346:381)
10/07 05:47:55.044 INFO |run_chromeos_tests:0052|       at Import.timedNamedFunction (chrome://tracing/tracing.js:573:310)
10/07 05:47:55.045 INFO |run_chromeos_tests:0052|       at Task.run (chrome://tracing/tracing.js:2062:13)


+nednguyen@, caseq@ because of Issue 632871, which at least superficially looks like a similar error, even though that one's on Win.  Any help or insight would be appreciated!