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ANGLE Wrangling

As an ANGLE Sheriff. Your job is fourfold:

  1. Keep the ANGLE Try Waterfall in good working order.
  2. Monitor the Chromium GPU FYI Waterfall and respond to ANGLE bugs.
  3. Control and monitor the ANGLE auto-roller.
  4. Keep the ANGLE Standalone Testers in good working order (follow link for instructions).
If you're not an ANGLE team member, you can contact us on the public ANGLE project Google group.

  Task 1: The Try Waterfall

Your most important job is to protect the health ANGLE Try Waterfall. Note that some failures are expected here;
devs might be testing their code to find bugs. Flakiness and unrelated failure, however, should be sought out and

Whenever you see an unexpected failure in your personal code, file a bug, or contact the current
ANGLE wrangler if you're not on duty. If the failure is outside of ANGLE, contact the GPU Pixel Wrangler for
assistance. Refer to's sheriff list to find the current GPU Wrangler.

NOTE: When everything is broken:

If there is a major infrastructure problem affecting multiple bots, use go/bug-a-trooper.

For filing new bugs, you can file either on the Chromium issue tracker or the ANGLE issue tracker as appropriate.

  Task 2: Respond to Bugs

The GPU Wrangler is primarily responsible for the Chromium GPU FYI Waterfall, but often ANGLE bugs pop up here
because of one-off bot configurations (currently the most common are angle_end2end_tests failures in Intel bots
on Windows).

Productivity Tip: Install the Chromium Buildbot Monitor extension.

IMPORTANT: Info to include in bug reports:
  • Links to all first failing builds (eg first windows failure, first mac failure, etc).
  • Link to a last passing build.
  • The Chromium and ANGLE regression ranges. See the note below on how to determine the ANGLE regression range.
  • Relevant errors.
  • Set components: usually Internals>GPU>Testing and/or Internals>GPU>ANGLE.
  • cc relevant sheriffs or blame suspects.

HOWTO: Determine the ANGLE regression range on the FYI bots:
  1. Open the first failing and last passing builds.
  2. For test failures: record 'parent_got_angle_revision' in both builds.
  3. For compile failures record 'got_angle_revision'.
  4. Use this URL:<last good revision>..<first bad revision>

  Task 3: The Auto-Roller

The ANGLE auto-roller automatically updates Chrome with the latest ANGLE changes. You have two jobs with the roller:
  1. You will be cc'ed on ANGLE rolls. If the roll fails, check quickly to verify there's no underlying ANGLE issue.
  2. IMPORTANT: You are responsible for pausing the roller 24h before branch days, and resuming afterwards. See the Chrome Release Schedule.

  Task 4: ANGLE Standalone Testing

See more detailed instructions on by following this link: ANGLE Standalone Testers.