All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=710187

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_MzbtwkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_IfI6AgM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_OO76QgM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_IecuQkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_JWDvwsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_NbeqAkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_LjW6AsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_JWDvwkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgvJf3ugsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_OO7qQsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgvJf3ugkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_JHiuQsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_MDS5goM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_JHiuQkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_IfIqAsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDggriSogoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgvPSx_AsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgvOGl4wkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgvKWDhggM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg3I-dzwkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_IzTrAoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgvNCm0AoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgvIfM5wgM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_PiTuwkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgvIPg6QoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_PiPpgoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg3I-dzwoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgvJnlxAgM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg3KnqzgsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg_PKOrAoM


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

chromium-rel-win7-dual
chromium-rel-win7-x64-dual

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8982664577998613568

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8982581308108865648

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

Hi guidou@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 : guidou
  Commit : 73d1c7107a41b474c6fed9292ff41f7ce3429a42
  Date   : Thu Apr 06 19:15:31 2017
  Subject: Enable spec-compliant algorithm for MediaStream video constraints by default

Bisect Details
  Configuration: win_x64_perf_bisect
  Benchmark    : performance_browser_tests
  Metric       : TabCapturePerformance_comp_gpu_novsync/CaptureSucceeded
  Change       : 91.84% | 16.9728755 -> 32.5612041667

Revision             Result                    N
chromium@462557      16.9729 +- 0.0812891      6      good
chromium@462571      17.0203 +- 0.352258       6      good
chromium@462573      17.0789 +- 0.322181       6      good
chromium@462574      17.089 +- 0.447167        6      good
chromium@462575      32.5007 +- 0.453057       6      bad       <--
chromium@462578      32.4954 +- 0.500672       6      bad
chromium@462584      32.5746 +- 0.738272       6      bad
chromium@462611      32.5009 +- 0.361095       6      bad
chromium@462664      32.4925 +- 0.347903       6      bad
chromium@462771      32.5217 +- 0.475307       6      bad
chromium@462985      32.5612 +- 0.466292       6      bad

To Run This Test
  .\src\out\Release_x64\performance_browser_tests.exe --test-launcher-print-test-stdio=always --enable-gpu

Debug Info
  https://chromeperf.appspot.com/buildbucket_job_status/8982664577998613568

Is this bisect wrong?
  https://chromeperf.appspot.com/bad_bisect?try_job_id=6173320770224128


| 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 Speed>Bisection.  Thank you!

The problem is that the new algorithm is not choosing the max frame rate, but using the default, so it is capturing at 30Hz instead of 60Hz with the old algorithm.
Preparing a patch to use the max frame rate as default, if provided.
Similar to a similar previous patch for the resolution.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/02fcf46036643c6c896c059161f2a2b6aa8e6c6b

commit 02fcf46036643c6c896c059161f2a2b6aa8e6c6b
Author: guidou <guidou@chromium.org>
Date: Wed Apr 12 17:31:14 2017

Update constraints algorithm for screen capture.

If explicit frame rate is given, use that as default. This is more
compatible with existing tests and applications and is still spec
compliant. This fixes a regression.

Use media::limits::kMaxDimension/2 (16383) as maximum screencast
dimension. The older value could produce results that exceed the
maximum canvas size, which is 16384 x 16384 - 1.

Properly use explicit maximum dimensions and frame rate as default in
screen capture. An older fix for dimensions had a bug when the maximum
allowed values coincided with explicitly given max constraints.

BUG= 657733 , 710187 

Review-Url: https://codereview.chromium.org/2814063002
Cr-Commit-Position: refs/heads/master@{#464068}

[modify] https://crrev.com/02fcf46036643c6c896c059161f2a2b6aa8e6c6b/content/renderer/media/media_stream_constraints_util_video_content.cc
[modify] https://crrev.com/02fcf46036643c6c896c059161f2a2b6aa8e6c6b/content/renderer/media/media_stream_constraints_util_video_content.h
[modify] https://crrev.com/02fcf46036643c6c896c059161f2a2b6aa8e6c6b/content/renderer/media/media_stream_constraints_util_video_content_unittest.cc

Thanks for the quick turnaround. The performance impact wasn't apparent last week because the perf bots were down/delayed.

Closing as fixed. Please reopen if this is not the case.