dtu@, you were looking into this test back in  bug 479337 , would you mind having a look again?

I append what seemed to be the relevant part of the log. The failing bots were win_chromium_x64_rel_ng and win_chromium_rel_ng.

Thanks!
Today's sheriff

[191/539] telemetry.internal.platform.power_monitor.msr_power_monitor_unittest.MsrPowerMonitorTest.testMsrRuns failed unexpectedly 0.0040s:
  Traceback (most recent call last):
    File "e:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\power_monitor\msr_power_monitor_unittest.py", line 19, in testMsrRuns
      if not power_monitor.CanMonitorPower():
    File "e:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\power_monitor\msr_power_monitor.py", line 134, in CanMonitorPower
      return self._CheckMSRs()
    File "e:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\power_monitor\msr_power_monitor.py", line 86, in _CheckMSRs
      if self._PackageEnergyJoules() <= 0:
    File "e:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\power_monitor\msr_power_monitor.py", line 73, in _PackageEnergyJoules
      return (self._backend.ReadMsr(MSR_PKG_ENERGY_STATUS, 0, 32) *
    File "e:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\win_platform_backend.py", line 398, in ReadMsr
      self._StartMsrServerIfNeeded()
    File "e:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\win_platform_backend.py", line 371, in _StartMsrServerIfNeeded
      _InstallWinRing0()
    File "e:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\win_platform_backend.py", line 75, in _InstallWinRing0
      cloud_storage.GetIfChanged(zip_path, bucket=cloud_storage.PUBLIC_BUCKET)
    File "e:\b\s\w\ir\third_party\catapult\common\py_utils\py_utils\cloud_storage.py", line 422, in GetIfChanged
      _GetLocked(bucket, expected_hash, file_path)
    File "e:\b\s\w\ir\third_party\catapult\common\py_utils\py_utils\cloud_storage.py", line 348, in _GetLocked
      _RunCommand(['cp', url, partial_download_path.name])
    File "e:\b\s\w\ir\third_party\catapult\common\py_utils\py_utils\cloud_storage.py", line 146, in _RunCommand
      'Command %s is not allowed to run' % args)
  CloudStorageIODisabled: Environment variable DISABLE_CLOUD_STORAGE_IO is set to 1. Command ['e:\\b\\depot_tools\\python276_bin\\python.exe', 'e:\\b\\s\\w\\ir\\third_party\\catapult\\third_party\\gsutil\\gsutil', 'cp', 'gs://chromium-telemetry/978305805fb52d838b3b4b09e9327da81f6973f7', 'e:\\b\\s\\w\\ir\\third_party\\catapult\\telemetry\\bin\\win\\AMD64\\tmpdru2je'] is not allowed to run

Randy: can you just remove this test? We should kill all these msr_power_monitor_unittest once Charlie is back 

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a1cd7531f9ca2c733d3d2399bce017853540e7b2

commit a1cd7531f9ca2c733d3d2399bce017853540e7b2
Author: catapult-deps-roller@chromium.org <catapult-deps-roller@chromium.org>
Date: Tue Apr 18 21:39:40 2017

Roll src/third_party/catapult/ 111b70975..e8775f0f6 (1 commit)

https://chromium.googlesource.com/external/github.com/catapult-project/catapult.git/+log/111b70975ab5..e8775f0f64bc

$ git log 111b70975..e8775f0f6 --date=short --no-merges --format='%ad %ae %s'
2017-04-18 rnephew [Telemetry] Disable flaky MSR power monitor unit test.

Created with:
  roll-dep src/third_party/catapult
BUG=712486


Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, see:
http://www.chromium.org/developers/tree-sheriffs/sheriff-details-chromium#TOC-Failures-due-to-DEPS-rolls


CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.android:android_optional_gpu_tests_rel
TBR=sullivan@chromium.org

Change-Id: I8f1f082dcc271485d613968a6b1e218d48e58b2e
Reviewed-on: https://chromium-review.googlesource.com/481220
Reviewed-by: <catapult-deps-roller@chromium.org>
Commit-Queue: <catapult-deps-roller@chromium.org>
Cr-Commit-Position: refs/heads/master@{#465384}
[modify] https://crrev.com/a1cd7531f9ca2c733d3d2399bce017853540e7b2/DEPS

Looks like a Dependency Manager issue

It's a an issue with the permission of the winring0 required to run msr_power_monitor not prefetched for some reason.