All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=755609

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=342421f1c96338f86f529c960911aefde2060cf25900c0a8fc1d8792a8653110


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

chromium-rel-mac-retina
chromium-rel-mac11
chromium-rel-mac11-pro

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8971173421098154864

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

Suspected Commit
  Author : ccameron chromium
  Commit : 28e0a3c183499e50b1b89231d4ed40bafb8883fe
  Date   : Fri Aug 11 04:59:46 2017
  Subject: Revert "Ensure overlapping compositor locks can time out"

Bisect Details
  Configuration: mac_pro_perf_bisect
  Benchmark    : page_cycler_v2.basic_oopif
  Metric       : timeToFirstContentfulPaint_avg/pcv1-cold/http___www.cnn.com
  Change       : 21.69% | 363.140799999 -> 441.89116667

Revision             Result                  N
chromium@493544      363.141 +- 37.1117      5      good
chromium@493609      365.768 +- 21.2667      6      good
chromium@493641      370.541 +- 24.7998      6      good
chromium@493657      366.662 +- 36.3288      6      good
chromium@493665      366.385 +- 37.3193      6      good
chromium@493669      365.922 +- 28.6881      6      good
chromium@493670      362.315 +- 32.6751      6      good
chromium@493671      442.589 +- 25.3892      6      bad       <--
chromium@493673      441.891 +- 22.273       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=http...www.cnn.com page_cycler_v2.basic_oopif

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8971173421098154864


For feedback, file a bug with component Speed>Bisection