All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=759465

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=8890face623c2f45d1c25b5e15a7165a781156247f821cc7300accd76cf5c6c7


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

android-webview-nexus5X
chromium-rel-mac11-pro
chromium-rel-win7-gpu-nvidia
chromium-rel-win7-x64-dual
chromium-rel-win8-dual

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8970030111130070704

=== Auto-CCing suspected CL author toyoshim@google.com ===

Hi toyoshim@google.com, 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 : Takashi Toyoshima
  Commit : b5985781e77b51eab38ef967c0f4466401fd80fd
  Date   : Mon Aug 21 12:08:09 2017
  Subject: Web MIDI: Check valid clients in MidiManager

Bisect Details
  Configuration: android_webview_arm64_aosp_perf_bisect
  Benchmark    : speedometer
  Metric       : jQuery-TodoMVC/jQuery-TodoMVC
  Change       : 1.65% | 4960.04559524 -> 5041.86666667

Revision             Result                  N
chromium@495876      4960.05 +- 184.86       14      good
chromium@495914      4911.97 +- 139.789      14      good
chromium@495917      4957.38 +- 146.133      14      good
chromium@495918      5003.84 +- 141.925      21      bad       <--
chromium@495919      5018.47 +- 153.971      14      bad
chromium@495924      5009.36 +- 123.063      6       bad
chromium@495933      4999.85 +- 76.4852      6       bad
chromium@495951      5027.63 +- 184.795      14      bad
chromium@496026      5026.34 +- 68.7069      9       bad
chromium@496175      5010.96 +- 144.278      14      bad
chromium@496473      5041.87 +- 102.268      9       bad

To Run This Test
  src/tools/perf/run_benchmark -v --browser=android-webview --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests speedometer

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8970030111130070704


For feedback, file a bug with component Speed>Bisection

this change itself does not have performance impact, and since this is a backend change that only affect Web MIDI API, it should not affect such benchmarks.

Let me kick another bisect.

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8969951454967625328

=== BISECT JOB RESULTS ===
Perf regression found but unable to narrow commit range

Build failures prevented the bisect from narrowing the range further.


Bisect Details
  Configuration: mac_pro_perf_bisect
  Benchmark    : v8.runtimestats.browsing_desktop
  Metric       : IC:duration_avg/browse_tech/browse_tech_discourse_infinite_scroll
  Change       : 5.52% | 373.369888889 -> 393.995444444

Suspected Commit Range
  3 commits in range
  https://chromium.googlesource.com/chromium/src/+log/e5d5eef46f948ec1aa28739ce6fda52e6a673f68..e330394483d1c796cbe2bd8ea1e27ebdc3f51a20


Revision             Result                  N
chromium@495876      373.37 +- 26.2343       9        good
chromium@496000      369.694 +- 20.5786      14       good
chromium@496033      367.338 +- 15.3952      6        good
chromium@496048      371.286 +- 27.0785      14       good
chromium@496057      370.798 +- 34.6255      21       good
chromium@496059      369.235 +- 41.0923      21       good
chromium@496060      ---                     ---      build failure
chromium@496061      ---                     ---      build failure
chromium@496062      378.072 +- 23.4062      14       bad
chromium@496123      393.995 +- 38.2494      9        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=browse.tech.discourse.infinite.scroll v8.runtimestats.browsing_desktop

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8969951454967625328


For feedback, file a bug with component Speed>Bisection