Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8975555842250881984

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

Suspected Commit
  Author : Ulan Degenbaev
  Commit : 5d8840e24e0e98136c081ee22441d808412d06e2
  Date   : Thu Jun 22 12:37:26 2017
  Subject: [runtime] Copy descriptors on prototype map transition.

Bisect Details
  Configuration: winx64nvidia_perf_bisect
  Benchmark    : v8.browsing_desktop
  Metric       : v8-gc-incremental-step_max/browse_social/browse_social_twitter
  Change       : 130.77% | 1.638 -> 3.78

Revision                           Result                   N
chromium@481571                    1.638 +- 0.4535          6      good
chromium@481584                    1.71183 +- 0.255755      6      good
chromium@481586                    1.76167 +- 0.539744      6      good
chromium@481586,v8@6681949808      1.65467 +- 0.374558      6      good
chromium@481586,v8@79ec067252      1.73167 +- 0.2311        6      good
chromium@481586,v8@5d8840e24e      3.55833 +- 2.23123       6      bad       <--
chromium@481587                    3.55867 +- 1.7643        6      bad
chromium@481588                    4.15917 +- 1.87224       6      bad
chromium@481591                    3.9695 +- 1.70031        6      bad
chromium@481597                    3.91567 +- 1.9433        6      bad
chromium@481623                    4.04467 +- 2.23578       6      bad
chromium@481674                    3.78 +- 1.60176          6      bad

To Run This Test
  src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=browse.social.twitter v8.browsing_desktop

Debug Info
  https://chromeperf.appspot.com/buildbucket_job_status/8975555842250881984

Is this bisect wrong?
  https://chromeperf.appspot.com/bad_bisect?try_job_id=6259280618979328


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