All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=638687

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgzqDe4wgM


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

android-nexus5

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9004055447558619632

===== BISECT JOB RESULTS =====
Status: failed


===== TESTED REVISIONS =====
Revision         Mean     Std Dev   N   Good?
chromium@411979  6.70343  0.178159  11  good
chromium@412026  6.89721  0.1003    8   bad

Bisect job ran on: android_nexus5_perf_bisect
Bug ID: 638687

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --also-run-disabled-tests media.android.tough_video_cases
Test Metric: cpu_utilization/crowd.wav_browser
Relative Change: 3.11%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus5_perf_bisect/builds/4009
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9004055447558619632


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5873640134934528

| 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!

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9003984100584467216

===== BISECT JOB RESULTS =====
Status: failed


===== TESTED REVISIONS =====
Revision         Mean     Std Dev   N   Good?
chromium@411979  6.70343  0.178159  11  good
chromium@412026  6.89721  0.1003    8   bad

Bisect job ran on: android_nexus5_perf_bisect
Bug ID: 638687

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --also-run-disabled-tests media.android.tough_video_cases
Test Metric: cpu_utilization/crowd.wav_browser
Relative Change: 3.11%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus5_perf_bisect/builds/4009
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9004055447558619632


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5873640134934528

| 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!

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9003959808039691200

Good revision doesn't have the expected lower mean (should be ~5.25 good vs 6.25 bad). I'm re-doing bisect with bigger range.

===== 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@411971  6.46416  0.180203  14  good
chromium@412130  6.53797  0.209319  12  bad

Bisect job ran on: android_nexus5_perf_bisect
Bug ID: 638687

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --also-run-disabled-tests media.android.tough_video_cases
Test Metric: cpu_utilization/crowd.wav_browser
Relative Change: 2.80%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus5_perf_bisect/builds/4014
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9003959808039691200


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5858510307328000

| 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!

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9003891046079530624

===== 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@411979  6.60358  0.161099  14  good
chromium@412026  6.59251  0.190153  12  bad

Bisect job ran on: android_nexus5_perf_bisect
Bug ID: 638687

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --also-run-disabled-tests media.android.tough_video_cases
Test Metric: cpu_utilization/crowd.wav_browser
Relative Change: 0.16%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus5_perf_bisect/builds/4012
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9004055447558619632


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5873640134934528

| 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!

Giving up - bisects aren't reproducing results from the graph. The graph had already recovered at the time I ran the bisects, so whatever the issue was seems to be resolved...