All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=623977

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg4ryxsgoM


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

chromium-rel-win8-dual

Moving this nonessential bug to the next milestone.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Trying another bisect.

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9007236926299114544

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9007236884281741200

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


=== Bisection aborted ===
The bisect was aborted because The metric values for the initial "good" and "bad" revisions do not represent a clear regression.
Please contact the the team (see below) if you believe this is in error.

=== Warnings ===
The following warnings were raised by the bisect job:

 * Bisect failed to reproduce the regression with enough confidence.

===== TESTED REVISIONS =====
Revision         Mean      Std Dev   N   Good?
chromium@402313  0.500998  0.225912  18  good
chromium@402339  0.627132  0.331474  18  bad

Bisect job ran on: win_8_perf_bisect
Bug ID: 623977

Test Command: .\src\out\Release\performance_browser_tests.exe --test-launcher-print-test-stdio=always --enable-gpu
Test Metric: CastV2Performance_gpu_60fps/video_jitter
Relative Change: 22.17%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/win_8_perf_bisect/builds/2028
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9007236926299114544


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5894134502522880

| 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!

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


=== Bisection aborted ===
The bisect was aborted because The metric values for the initial "good" and "bad" revisions do not represent a clear regression.
Please contact the the team (see below) if you believe this is in error.

=== Warnings ===
The following warnings were raised by the bisect job:

 * Bisect failed to reproduce the regression with enough confidence.

===== TESTED REVISIONS =====
Revision         Mean      Std Dev   N   Good?
chromium@402313  0.607976  0.227967  18  good
chromium@402324  0.57339   0.232796  18  bad

Bisect job ran on: win_8_perf_bisect
Bug ID: 623977

Test Command: .\src\out\Release\performance_browser_tests.exe --test-launcher-print-test-stdio=always --enable-gpu
Test Metric: CastV2Performance_gpu_60fps/video_jitter
Relative Change: 55.76%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/win_8_perf_bisect/builds/2029
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9007236884281741200


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5855560008728576

| 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!

The improvement seems temporary, and now it is back to before.