All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=753980

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=a96addc1945677da13b8857ee4f0351d1d589e2e31a5aa477cc9427b5ebd0c3d


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

android-nexus6
chromium-rel-mac-retina
chromium-rel-mac11
chromium-rel-mac12
chromium-rel-mac12-mini-8gb
chromium-rel-win10
chromium-rel-win7-gpu-ati
chromium-rel-win7-gpu-intel
chromium-rel-win7-gpu-nvidia

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8971703448929700544

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

Hi ulan@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 : Ulan Degenbaev
  Commit : feb3ee40d03137ffcc2be98a01f6ea936cdf45e1
  Date   : Mon Aug 07 16:21:24 2017
  Subject: [heap] Disable parallel scavenge.

Bisect Details
  Configuration: mac_retina_perf_bisect
  Benchmark    : memory.long_running_idle_gmail_tbmv2
  Metric       : v8-gc-scavenger_max/v8-gc-scavenger_max
  Change       : 246.51% | 4.41083333333 -> 15.2838333333

Revision                           Result                   N
chromium@492365                    4.41083 +- 0.390452      6      good
chromium@492414                    4.5095 +- 1.27213        6      good
chromium@492439                    4.52467 +- 1.72235       6      good
chromium@492442                    4.396 +- 0.383927        6      good
chromium@492444                    4.3855 +- 0.534151       6      good
chromium@492444,v8@a7a166e30c      4.64817 +- 0.882777      6      good
chromium@492444,v8@ceb55494bd      4.51133 +- 0.701886      6      good
chromium@492444,v8@feb3ee40d0      15.3075 +- 3.18234       6      bad       <--
chromium@492444,v8@864837ff3c      14.6245 +- 1.07941       6      bad
chromium@492445                    14.5082 +- 1.99234       6      bad
chromium@492451                    14.4163 +- 2.24659       6      bad
chromium@492463                    15.2838 +- 2.34091       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 memory.long_running_idle_gmail_tbmv2

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8971703448929700544


For feedback, file a bug with component Speed>Bisection

 Issue 753984  has been merged into this issue.

 Issue 753981  has been merged into this issue.

 Issue 753998  has been merged into this issue.

 Issue 754625  has been merged into this issue.

Parallel marking was re-enabled.