All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=694550

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-MGztQoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-LfStgkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDguI3LjAkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-NHy5wsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDghMavpAoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDghMazuQoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-LnuowoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-ID-igoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-OCm5goM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-P6LowkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-J3MqQoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-P6fsgoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDguJzb1gkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDguO7h9AsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-Jne-wgM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-OnCuQkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-IbYsAkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDghMTOvwoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDguI_trAoM


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

android-nexus5
android-nexus5X
android-nexus6
android-nexus7v2
chromium-rel-mac-retina
chromium-rel-mac11
chromium-rel-mac11-air
chromium-rel-mac11-pro
chromium-rel-mac12
chromium-rel-mac12-mini-8gb
chromium-rel-win10
chromium-rel-win7-dual
chromium-rel-win7-gpu-ati
chromium-rel-win7-gpu-intel
chromium-rel-win7-gpu-nvidia
chromium-rel-win7-x64-dual
linux-release
win-high-dpi
win-zenbook

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8987040885803840192

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8987040837578151440

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

Hi jinsukkim@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 : jinsukkim
  Commit : 89967f02f2402870acb8322ad50c391b3a0971e7
  Date   : Fri Feb 17 02:38:21 2017
  Subject: Do not guess UTF8 encoding

Bisect Details
  Configuration: linux_perf_bisect
  Benchmark    : blink_perf.layout
  Metric       : hindi-line-layout/hindi-line-layout
  Change       : 56.82% | 284.65194938 -> 122.922967524

Revision             Result                  N
chromium@451148      284.652 +- 64.0769      6      good
chromium@451174      297.48 +- 11.1977       6      good
chromium@451187      299.271 +- 6.5067       6      good
chromium@451191      298.808 +- 9.98313      6      good
chromium@451193      291.605 +- 34.5596      5      good
chromium@451194      126.183 +- 9.92366      6      bad       <--
chromium@451200      126.819 +- 4.04977      6      bad
chromium@451251      122.923 +- 8.40309      6      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 blink_perf.layout

Debug Info
  https://chromeperf.appspot.com/buildbucket_job_status/8987040885803840192

Is this bisect wrong?
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5111194005798912


| 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!

Just landed https://crbug.com/2706883002 I'll monitor the graph and will take a look if it doesn't rectify the regression.

=== BISECT JOB RESULTS ===
Bisect was unable to run to completion

Please try rerunning the bisect.


If failures persist contact the team (see below) and report the error.


Bisect Details
  Configuration: android_nexus6_perf_bisect
  Benchmark    : blink_perf.layout
  Metric       : hindi-line-layout/hindi-line-layout

Revision             Result                   N
chromium@451189      34.2282 +- 0.696077      6      good
chromium@451201      11.3397 +- 0.191116      6      bad

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

Debug Info
  https://chromeperf.appspot.com/buildbucket_job_status/8987040837578151440

Is this bisect wrong?
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5505751310663680


| 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!

There are other Hindi layout test htmls that needs updating. Looking into that...

The fix is up for review https://crrev.com/2716553002. Local benchmark test shows that it addresses the issue:

./tools/perf/run_benchmark --browser-executable=out.linux/Release/chrome --output-format=json blink_perf.layout --pageset-repeat=3  --story-filter=hindi-line-layout

Description: Measures performance of layout on a page containing Hindi.


Time:
values 4.124264076628827, 3.9732731161718835, 4.0366935443178535, 4.005206768799436, 3.7987185656038664 runs/s
avg 3.9876312143043737 runs/s
median 4.005206768799436 runs/s
stdev 0.11966483947901814 runs/s
min 3.7987185656038664 runs/s
max 4.124264076628827 runs/s

improved to:

Time:
values 8.8548749248917, 8.990091634719763, 8.772039749871544, 9.206952564465086, 8.796124678784413 runs/s
avg 8.924016710546502 runs/s
median 8.8548749248917 runs/s
stdev 0.17934084024902675 runs/s
min 8.772039749871544 runs/s
max 9.206952564465086 runs/s

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e9bfe75886f49ffe347787389b7346dba85a313a

commit e9bfe75886f49ffe347787389b7346dba85a313a
Author: jinsukkim <jinsukkim@chromium.org>
Date: Thu Feb 23 03:55:09 2017

Explicitly set charset to Blink perf resource hindi-line-layout.html

A recent change https://crrev.com/2697213002 caused a regression
in one Blink layout performance test. This CL fixes it by setting
the encoding label explicitly in the test html to prevent the result
from being affected by the text in it rendered wrongly.

BUG= 694550 

Review-Url: https://codereview.chromium.org/2716553002
Cr-Commit-Position: refs/heads/master@{#452382}

[modify] https://crrev.com/e9bfe75886f49ffe347787389b7346dba85a313a/third_party/WebKit/PerformanceTests/Layout/hindi-line-layout.html

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8982612134458186944