All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=639311

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgrsKT5gkM


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

chromium-rel-win10

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9003888109857372528

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

Hi mlippautz@chromium.org, the bisect results pointed to your CL below as possibly
causing a regression. Please have a look at this info and see whether
your CL be related.


===== BISECT JOB RESULTS =====
Status: completed


===== SUSPECTED CL(s) =====
Subject : [heap] Improve size profiling for ArrayBuffer tracking
Author  : mlippautz
Commit description:
  
Eagerly account for retained sizes during ArrayBuffer tracking. Following up on this,
we can now do Scavenges if the amount of memory retained from new space is too large.

BUG=chromium:621829
R=jochen@chromium.org,hpayer@chromium.org

Review-Url: https://codereview.chromium.org/2210263002
Cr-Commit-Position: refs/heads/master@{#38731}
Commit  : 28e13bd6a75c9467dae43043e7b741a1387d5252
Date    : Thu Aug 18 20:45:43 2016


===== TESTED REVISIONS =====
Revision                       Mean   Std Dev   N   Good?
chromium@413020                3.0    0.0       12  good
chromium@413021                3.0    0.0       8   good
chromium@413021,v8@255971d3ac  3.0    0.0       8   good
chromium@413021,v8@28e13bd6a7  3.75   0.46291   8   bad    <--
chromium@413022                3.625  0.517549  8   bad
chromium@413023                3.625  0.517549  8   bad
chromium@413026                3.8    0.447214  5   bad
chromium@413031                3.8    0.447214  5   bad
chromium@413042                3.5    0.534522  8   bad

Bisect job ran on: winx64_10_perf_bisect
Bug ID: 639311

Test Command: src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --also-run-disabled-tests v8.detached_context_age_in_gc
Test Metric: V8_DetachedContextAgeInGC/https___www.google.com__hl_en_q_barack+obama
Relative Change: 13.33%
Score: 98.0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/winx64_10_perf_bisect/builds/666
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9003888109857372528


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5890574855438336

| O O | Visit http://www.chromium.org/developers/speed-infra/perf-bug-faq
|  X  | for more information addressing perf regression bugs. For feedback,
| / \ | file a bug with component Tests>AutoBisect.  Thank you!

 Issue 639310  has been merged into this issue.

CL in question has already been reverted. Will take a closer look before relanding.