All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=627089

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgstOJvgoM


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

android-nexus9

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


=== Bisection aborted ===
The bisect was aborted because The metric values for the initial "good" and "bad" revisions do not represent a clear regression.
Please contact the the team (see below) if you believe this is in error.

=== Warnings ===
The following warnings were raised by the bisect job:

 * Bisect failed to reproduce the regression with enough confidence.

===== TESTED REVISIONS =====
Revision         Mean     Std Dev    N   Good?
chromium@404312  1.60751  0.0548012  12  good
chromium@404314  1.61493  0.0492835  18  bad

Bisect job ran on: android_nexus9_perf_bisect
Bug ID: 627089

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --also-run-disabled-tests thread_times.key_silk_cases
Test Metric: thread_renderer_compositor_cpu_time_per_frame/thread_renderer_compositor_cpu_time_per_frame
Relative Change: 0.99%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus9_perf_bisect/builds/1879
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9007428541094535344


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5900273168416768

| 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!

Probably one of:
https://codereview.chromium.org/2101163002 (rockot@)
https://chromium.googlesource.com/external/khronosgroup/webgl.git/+log/ae375e0..fe43b3c (+zmo@)

Assigning to rockot@, as that seems much more likely.

Perf sheriff ping: reminder to follow up on possible performance issues

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9000694794782898160

Kicked off a wider bisect.

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


=== Bisection aborted ===
The bisect was aborted because The metric values for the initial "good" and "bad" revisions do not represent a clear regression.
Please contact the the team (see below) if you believe this is in error.

=== Warnings ===
The following warnings were raised by the bisect job:

 * Bisect failed to reproduce the regression with enough confidence.

===== TESTED REVISIONS =====
Revision         Mean     Std Dev    N   Good?
chromium@404166  1.54854  0.0444953  18  good
chromium@404314  1.59235  0.0481466  18  bad

Bisect job ran on: android_nexus9_perf_bisect
Bug ID: 627089

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --also-run-disabled-tests thread_times.key_silk_cases
Test Metric: thread_renderer_compositor_cpu_time_per_frame/thread_renderer_compositor_cpu_time_per_frame
Relative Change: 3.23%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus9_perf_bisect/builds/2120
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9000694794782898160


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5862091754307584

| 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!

Fixit ping. rockot: can you see whether your CL mentioned in comment 3 is related? zmo: how about yours in the same comment?

I'll kick off another bisect in the meantime.

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8999612152379935312

Bisect failed: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus9_perf_bisect/builds/2160
Failure reason: the build has failed.
Additional errors:
The metric was not found in the test output.
Either of the initial "good" or "bad" revisions failed to be tested or built.

ping - please respond to comment#8.

Probably yes. CPU cost of IPC has gone up a little.

Yeah, I talked to Annie about this (I'm still learning how to sheriff these). We agreed that this isn't really worth our time to continue debugging. Closing as wontfix.

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8982619868177313584