All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=768293

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=34cc15509aa15eb427aa80489b5fc076be35d9540a1d609be43fb878acd3d463


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

chromium-rel-mac-retina
chromium-rel-mac11
chromium-rel-mac11-air
chromium-rel-mac12
chromium-rel-mac12-mini-8gb
chromium-rel-win8-dual
win-high-dpi

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8967498693298150368

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

Suspected Commit
  Author : Ulan Degenbaev
  Commit : a76d0a771e430dbc8716624febc549aede738d96
  Date   : Thu Sep 21 12:35:10 2017
  Subject: Reland "[heap] Enable concurrent marking for x86 and x64."

Bisect Details
  Configuration: mac_retina_perf_bisect
  Benchmark    : oortonline_tbmv2
  Metric       : memory:chrome:renderer_processes:reported_by_chrome:v8:heap:allocated_objects_size_max/http___oortonline.gl__run
  Change       : 37.86% | 324476192.0 -> 447309525.333

Revision                           Result                     N
chromium@503432                    324476192 +- 91492.4       6      good
chromium@503476                    324469681 +- 192340        6      good
chromium@503487                    324494205 +- 217614        6      good
chromium@503490                    324462593 +- 148630        6      good
chromium@503491                    324452193 +- 154209        6      good
chromium@503491,v8@2857dab5cb      324426853 +- 198140        6      good
chromium@503491,v8@a76d0a771e      445091284 +- 7916180       6      bad       <--
chromium@503492                    441385708 +- 18559878      6      bad
chromium@503493                    446153687 +- 6048949       6      bad
chromium@503498                    446336896 +- 6024385       6      bad
chromium@503520                    447309525 +- 1258411       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...oortonline.gl..run oortonline_tbmv2

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8967498693298150368


For feedback, file a bug with component Speed>Bisection