All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=792453

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=9031996bc2e1fb371885d58470c3af5b9d1483977fcf39e8f02506dd85df0c8a


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

android-nexus5
android-nexus7v2
android-webview-nexus5X
android-webview-nexus6

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8960949385328476800

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

Suspected Commit
  Author : Chris Harrelson
  Commit : a3e4477c29d087d3708dbcb4dc5a90985c2b45e3
  Date   : Tue Dec 05 01:51:58 2017
  Subject: [PE] Turn on half-width tiles for all platforms and devices.

Bisect Details
  Configuration: android_webview_arm64_aosp_perf_bisect
  Benchmark    : thread_times.key_silk_cases
  Metric       : thread_raster_cpu_time_per_frame/silk_finance.html
  Change       : 57.53% | 0.906425899835 -> 1.42786009745

Revision             Result                     N
chromium@521550      0.906426 +- 0.0926225      6      good
chromium@521580      0.923673 +- 0.0111368      6      good
chromium@521584      0.894899 +- 0.0480232      6      good
chromium@521585      0.906618 +- 0.0521489      6      good
chromium@521586      1.44932 +- 0.043509        6      bad       <--
chromium@521588      1.42939 +- 0.0907698       6      bad
chromium@521595      1.46228 +- 0.0379926       6      bad
chromium@521609      1.42786 +- 0.0651893       6      bad

To Run This Test
  src/tools/perf/run_benchmark -v --browser=android-webview --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=silk.finance.html thread_times.key_silk_cases

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8960949385328476800


For feedback, file a bug with component Speed>Bisection