All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=629891

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg6sX1vgoM


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

win-zenbook

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9006596723537681040

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

Hi varkha@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 : [ash-md] Improves smoothness with many windows in overview
Author  : varkha
Commit description:
  
Experimentally, most of the animation cost was coming from having window
shapes (used to mask the window header) and from using rounded rectangle
masks.
This CL disables both those performance hogs when there are more than
certain number of windows in the overview mode (controlled via flags).
Default is set to hardcoded 10.
It also makes sure that window controls (minimize / resize / close) are
hidden when in overview mode for custom and panel frames.

New flags are introduced:

--ash-max-previews-to-use-mask=<number>
Maximum number of preview windows in overview mode that can use masks to
hide window headers and use rounded corners. Use -1 to set to unlimited.

--ash-max-previews-to-use-shape=<number>
Maximum number of preview windows in overview mode that can use shapes to
hide window headers. Use -1 to set to unlimited.

BUG= 626851 
BUG= 624608 

Review-Url: https://codereview.chromium.org/2146323004
Cr-Commit-Position: refs/heads/master@{#406286}
Commit  : d8748a3907d55ade9282b8cf4d0993ac9ee5ab66
Date    : Tue Jul 19 16:05:10 2016


===== TESTED REVISIONS =====
Revision         Mean     Std Dev   N  Good?
chromium@406264  59.2609  2.63807   5  good
chromium@406276  62.5292  0.979702  5  good
chromium@406282  59.4425  0.200755  5  good
chromium@406285  62.9132  0.163446  5  good
chromium@406286  50.7305  0.104337  5  bad    <--
chromium@406287  48.1261  1.89286   5  bad

Bisect job ran on: winx64_zen_perf_bisect
Bug ID: 629891

Test Command: src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --also-run-disabled-tests blink_perf.layout
Test Metric: hindi-line-layout/hindi-line-layout
Relative Change: 18.79%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/winx64_zen_perf_bisect/builds/283
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9006596723537681040


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5877572504649728

| 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!

Not really possible since my change was only in ash and wouldn't get compiled into chrome on Win bots.

The metric has recovered, I think we can close this.