All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=775944

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=598f7e25c62269b4c45a1f55abf28d4f4ef2dbe3333455a7888e40a062cfe5c2


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

chromium-rel-mac-retina

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8965385907255912336

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8965385858780984016

The regression is very gradual. Started a bisect job with a wide range.

=== BISECT JOB RESULTS ===
Bisect failed for unknown reasons

Please contact the team (see below) and report the error.


Bisect Details
  Configuration: mac_retina_perf_bisect
  Benchmark    : system_health.common_desktop
  Metric       : cpu_time_percentage_avg/load_accessibility_shopping/load_accessibility_shopping_amazon


To Run This Test
  src/tools/perf/run_benchmark -v --browser=release --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=load.accessibility.shopping.amazon system_health.common_desktop

More information on addressing performance regressions:
  http://g.co/ChromePerformanceRegressions

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8965385907255912336


For feedback, file a bug with component Speed>Bisection

Will wait for the 2nd bisect job.

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

Hi nektar@chromium.org, the bisect results pointed to your CL, please take a look at the
results.


=== BISECT JOB RESULTS ===
Perf regression found with culprit

Suspected Commit
  Author : Nektarios Paisios
  Commit : 2c8739dff9cd72a0a8d4325fc6d26393df882bb0
  Date   : Mon Oct 09 17:41:57 2017
  Subject: Stops ignoring clickable elements.

Bisect Details
  Configuration: mac_retina_perf_bisect
  Benchmark    : system_health.common_desktop
  Metric       : cpu_time_percentage_avg/load_accessibility_shopping/load_accessibility_shopping_amazon
  Change       : 8.84% | 0.203324065425 -> 0.220716585743

Revision             Result                      N
chromium@507326      0.203324 +- 0.0189952       14      good
chromium@507390      0.204381 +- 0.0222597       21      good
chromium@507398      0.202381 +- 0.0103044       9       good
chromium@507400      0.202568 +- 0.0146716       14      good
chromium@507401      0.207523 +- 0.017227        13      bad       <--
chromium@507402      0.209268 +- 0.0115428       9       bad
chromium@507406      0.208285 +- 0.00688457      9       bad
chromium@507422      0.21152 +- 0.00573491       6       bad
chromium@507453      0.210267 +- 0.0173531       14      bad
chromium@507580      0.211054 +- 0.0107255       9       bad
chromium@507833      0.216123 +- 0.0072092       6       bad
chromium@508339      0.220717 +- 0.0103642       6       bad

To Run This Test
  src/tools/perf/run_benchmark -v --browser=release --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=load.accessibility.shopping.amazon system_health.common_desktop

More information on addressing performance regressions:
  http://g.co/ChromePerformanceRegressions

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8965385858780984016


For feedback, file a bug with component Speed>Bisection

 Issue 773836  has been merged into this issue.

For triaging.

nektar@, leberly@: what is the status on this? In particular should we revert the suspected CL while you are looking into a fix?

For example this has caused ~30% regression in: 
browser_accessibility_events_avg/load_accessibility_shopping/load_accessibility_shopping_amazon	

I am not sure how that translated to actual ens-user perceived regression but it seems bad on surface. cc system_health.common_desktop owners for awareness.

nektar@, leberly@: ping on #12?

Looks like we'll need to accept the regression at this point.