All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=659168

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgvfHUowoM


Bot(s) for this bug's original alert(s):

android-nexus5X

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8997815233872479840

=== Auto-CCing suspected CL author zmo@chromium.org ===

Hi zmo@chromium.org, the bisect results pointed to your CL below as possibly
causing a regression. Please have a look at this info and see whether
your CL be related.


===== BISECT JOB RESULTS =====
Status: completed


===== SUSPECTED CL(s) =====
Subject : Initialize buffers before allowing access to them.
Author  : zmo
Commit description:
  
Also, refactor buffer access validation a bit to reduce
duplicated codes.

(Note that this is still part 1 of the work. We have more
buffer access paths that we need to put in buffer access
validation.)

BUG= 654201 
TEST=gpu_unittests, webgl_conformance
R=piman@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2435803004
Cr-Commit-Position: refs/heads/master@{#427200}
Commit  : 26c35c2e81f97a5b291ebd4d639fc3f1a4cc50e8
Date    : Tue Oct 25 01:03:34 2016


===== TESTED REVISIONS =====
Revision         Mean     Std Dev    N  Good?
chromium@427182  2.91441  0.0502254  5  good
chromium@427193  2.87573  0.0232682  5  good
chromium@427199  2.95709  0.0609555  5  good
chromium@427200  3.24093  0.0145801  5  bad    <--
chromium@427201  3.27781  0.0295023  5  bad
chromium@427202  3.29082  0.0743062  5  bad
chromium@427204  3.21492  0.0175714  5  bad

Bisect job ran on: android_nexus5X_perf_bisect
Bug ID: 659168

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests thread_times.simple_mobile_sites
Test Metric: thread_GPU_cpu_time_per_frame/thread_GPU_cpu_time_per_frame
Relative Change: 10.31%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus5X_perf_bisect/builds/793
Job details: https://chromeperf.appspot.com/buildbucket_job_status/8997815233872479840


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5244086276063232

| O O | Visit http://www.chromium.org/developers/speed-infra/perf-bug-faq
|  X  | for more information addressing perf regression bugs. For feedback,
| / \ | file a bug with component Tests>AutoBisect.  Thank you!

Friendly perf-sheriff ping - zmo@ could you take a look and revert the CL if there isn't an easy fix to this regression.

Looks like this came back down in November.