All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=670793

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgx4T0qQkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgp7i_sAoM


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

android-nexus6
android-one

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8994362893409969584

=== PERF REGRESSION ===


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

Hi jgruber@chromium.org, the bisect results pointed to your CL, please take a look at the
results.


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


===== SUSPECTED CL(s) =====
Subject : [regexp] Refactor RegExp.prototype.exec
Author  : jgruber
Commit description:
  
This refactors portions of exec into a new function without RegExpResult
construction, which will be used in the future by test, @@match, and @@search
fast paths.

Unnecessary ToString and ToLength calls as well as repeated map checks were
removed.

BUG= v8:5339 

Review-Url: https://codereview.chromium.org/2540153002
Cr-Commit-Position: refs/heads/master@{#41414}
Commit  : 65b2ab90ff1cbc90f73568c7ec9d72cb760ac6c8
Date    : Thu Dec 01 09:36:08 2016


===== TESTED REVISIONS =====
Revision                       Mean     Std Dev  N  Good?
chromium@435598                2265670  12926.5  8  good
chromium@435599                2272766  28893.8  8  good
chromium@435599,v8@91ea744c74  2272245  38406.5  8  good
chromium@435599,v8@65b2ab90ff  2304002  29090.0  8  bad    <--
chromium@435599,v8@a328143eb3  2299826  27279.4  8  bad
chromium@435600                2307196  14156.8  5  bad
chromium@435601                2297362  28842.5  5  bad
chromium@435603                2305347  11913.2  5  bad
chromium@435608                2301261  22029.1  5  bad

Bisect job ran on: android_one_perf_bisect
Bug ID: 670793

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=https.m.facebook.com.rihanna memory.top_10_mobile
Test Metric: memory:chrome:all_processes:reported_by_chrome:v8:effective_size_avg/background/after_https_m_facebook_com_rihanna
Relative Change: 1.57%

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_one_perf_bisect/builds/1843
Job details: https://chromeperf.appspot.com/buildbucket_job_status/8994362893409969584


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5238796105285632

| 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!

Given that that CL description says it's refactoring, and 	memory.top_10_mobile has been giving us some false alerts recently, I think that's an unlikely cause.

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8993988169338725488

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


===== SUSPECTED CL(s) =====
Subject : [regexp] Migrate @@split to TurboFan
Author  : jgruber
Commit description:
  
This shows around a 2.2x speedup compared to the old JS implementation (and
3.5x compared to CPP) for the fast path.

Adds ToUint32 to CodeStubAssembler.

BUG= v8:5339 

Review-Url: https://codereview.chromium.org/2532403002
Cr-Commit-Position: refs/heads/master@{#41408}
Commit  : 2c3fe6d961e4a496bf5edc33a14c5c09245185c9
Date    : Thu Dec 01 08:25:20 2016


===== TESTED REVISIONS =====
Revision                       Mean     Std Dev  N   Good?
chromium@435553                4841453  31309.7  8   good
chromium@435581                4847821  211.641  8   good
chromium@435595                4843579  33034.5  12  good
chromium@435595,v8@6b9c49cac1  4847826  326.288  8   good
chromium@435595,v8@2c3fe6d961  4872110  277.22   5   bad    <--
chromium@435595,v8@48a522b643  4867554  42545.0  18  bad
chromium@435596                4872065  1561.61  12  bad
chromium@435597                4868785  25404.7  8   bad
chromium@435599                4872142  272.094  5   bad
chromium@435602                4913309  169.932  5   bad
chromium@435608                4913275  210.325  5   bad

Bisect job ran on: android_nexus9_perf_bisect
Bug ID: 670793

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=https.mobile.twitter.com.justinbieber.skip.interstitial.true memory.top_10_mobile
Test Metric: memory:chrome:all_processes:reported_by_chrome:v8:effective_size_avg/background/after_https_mobile_twitter_com_justinbieber_skip_interstitial_true
Relative Change: 1.48%

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus9_perf_bisect/builds/2309
Job details: https://chromeperf.appspot.com/buildbucket_job_status/8993988169338725488


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5814819100295168

| 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!