All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=661519

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgg9y7vAkM


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

android-nexus5

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8997110019708319120

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


===== TESTED REVISIONS =====
Revision         Mean     Std Dev  N   Good?
chromium@428117  773.024  28.1367  12  good
chromium@428135  770.957  19.2536  8   good
chromium@428144  753.457  35.4782  12  good
chromium@428146  837.436  74.8318  12  bad
chromium@428147  842.223  71.8481  12  bad
chromium@428149  860.903  52.1011  4   bad
chromium@428153  857.853  73.7981  8   bad
chromium@428189  852.369  75.3459  8   bad

Bisect job ran on: android_nexus5_perf_bisect
Bug ID: 661519

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests page_cycler_v2.tough_layout_cases
Test Metric: timeToFirstContentfulPaint_avg/pcv1-cold/http___mydiyclub.com
Relative Change: 6.97%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus5_perf_bisect/builds/4312
Job details: https://chromeperf.appspot.com/buildbucket_job_status/8997110019708319120


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5515361724661760

| 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/8996917683630128544

Bisect failed: http://build.chromium.org/p/tryserver.chromium.perf/builders/linux_perf_bisect/builds/6818
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.

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8996639109690603632

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


===== SUSPECTED CL(s) =====
Subject : Add field trial config for CSSExternalScanner experiment
Author  : csharrison
Commit description:
  
BUG= 596676 

Review-Url: https://codereview.chromium.org/2454823004
Cr-Commit-Position: refs/heads/master@{#428146}
Commit  : 90f9f786e88b196d391e6daffb4c9ab7ca7087ab
Date    : Thu Oct 27 21:33:49 2016


===== TESTED REVISIONS =====
Revision         Mean     Std Dev  N   Good?
chromium@428134  677.289  195.355  12  good
chromium@428141  614.847  5.12472  8   good
chromium@428144  604.095  5.60483  5   good
chromium@428145  604.322  7.67899  4   good
chromium@428146  791.523  91.0757  5   bad    <--
chromium@428147  804.607  77.6597  8   bad
chromium@428160  825.153  12.1104  5   bad
chromium@428186  827.474  20.0159  5   bad
chromium@428238  769.051  115.092  12  bad

Bisect job ran on: linux_perf_bisect
Bug ID: 661519

Test Command: src/tools/perf/run_benchmark -v --browser=release --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=http...bookish.com page_cycler_v2.tough_layout_cases
Test Metric: timeToFirstMeaningfulPaint_avg/pcv1-cold/http___bookish.com
Relative Change: 10.81%
Score: 98.0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/linux_perf_bisect/builds/6822
Job details: https://chromeperf.appspot.com/buildbucket_job_status/8996639109690603632


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5018881926627328

| 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/8982612101798604832

=== BISECT JOB RESULTS ===
Perf regression found but unable to narrow commit range

Build failures prevented the bisect from narrowing the range further.


Bisect Details
  Configuration: android_nexus5_perf_bisect
  Benchmark    : page_cycler_v2.tough_layout_cases
  Metric       : timeToFirstContentfulPaint_avg/pcv1-cold/http___mydiyclub.com

Suspected Commit Range
  1 commits in range
  https://chromium.googlesource.com/chromium/src/+log/d057ec8ca382747f8b3de68255b8fa735fdc2d7e..90f9f786e88b196d391e6daffb4c9ab7ca7087ab


Revision             Result                  N
chromium@428117      773.024 +- 28.1367      12      good
chromium@428135      770.957 +- 19.2536      8       good
chromium@428144      753.457 +- 35.4782      12      good
chromium@428146      837.436 +- 74.8318      12      bad
chromium@428147      842.223 +- 71.8481      12      bad
chromium@428149      860.903 +- 52.1011      4       bad
chromium@428153      857.853 +- 73.7981      8       bad
chromium@428189      852.369 +- 75.3459      8       bad

To Run This Test
  src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests page_cycler_v2.tough_layout_cases

Debug Info
  https://chromeperf.appspot.com/buildbucket_job_status/8982612101798604832

Is this bisect wrong?
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5515361724661760


| 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 Speed>Bisection.  Thank you!