All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=633179

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg-qzruAkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg-sXyowsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICghqjhvwoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg-uOUtwsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg-ovMrgoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg-pXB9wgM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICghr77rAoM


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

chromium-rel-mac-retina
chromium-rel-win10
chromium-rel-win7-dual
chromium-rel-win7-gpu-ati
chromium-rel-win7-gpu-intel
chromium-rel-win7-gpu-nvidia

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9005529982773423920

===== 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@407738  1061336  0.0      12  good
chromium@407755  930717   369446   8   bad

Bisect job ran on: mac_retina_perf_bisect
Bug ID: 633179

Test Command: src/tools/perf/run_benchmark -v --browser=release --output-format=chartjson --upload-results --also-run-disabled-tests system_health.memory_desktop
Test Metric: load_tools-memory:chrome:all_processes:reported_by_chrome:v8:allocated_by_malloc:effective_size_avg/load_tools_stackoverflow
Relative Change: 19.69%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/mac_retina_perf_bisect/builds/1495
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9005529982773423920


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5805746348883968

| 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!

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9005164539772690976

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


===== SUSPECTED CL(s) =====
Subject : Unify glyph metrics to use the same Skia API
Author  : drott
Commit description:
  
Use identical glyph metrics based bounds in HarfBuzz callbacks as well
as ShapeResult's glyph bounds calculation, except on Mac, due to Skia
bug https://bugs.chromium.org/p/skia/issues/detail?id=5328

* Using the same glyph bounds callback in HarfBuzz shaping and in
  ShapeResult's glyph bounds calculation enables reusing of the same
  cache in Skia, as opposed to using the cached glyph metrics based
  cache vs. using a second cache for path based metrics before.

Local benchmarking of the blink_perf.layout shows 12.44%
improvements for the character_fallback test and 1.8-5%
improvements on chapter-reflow-once, line-layout and
latin-complex-test. There are also some hits on flexbox-lots of
data and flexbox-row-nowrap. I am not 100% convinced that the
local benchmarks are accurate enough and would like to observe
the results on the bot. Overall, we should see a layout speed
improvement, perhaps even in the page cyclers.

BUG= 610313 
R=kojii,tzik

Review-Url: https://codereview.chromium.org/1980913002
Cr-Commit-Position: refs/heads/master@{#407755}
Commit  : 9e47ba024f0061ea667565451c2842f66813fee7
Date    : Tue Jul 26 09:59:36 2016


===== TESTED REVISIONS =====
Revision         Mean     Std Dev  N  Good?
chromium@407699  9112083  37718.8  5  good
chromium@407747  9118636  16987.3  5  good
chromium@407754  9113721  19856.1  5  good
chromium@407755  9228409  19856.1  5  bad    <--
chromium@407756  9233324  25480.9  5  bad
chromium@407757  9242335  16281.3  5  bad
chromium@407760  9217759  25348.9  5  bad
chromium@407769  9230867  21981.4  5  bad
chromium@407791  9245612  31780.3  5  bad

Bisect job ran on: winx64ati_perf_bisect
Bug ID: 633179

Test Command: src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --also-run-disabled-tests system_health.memory_desktop
Test Metric: load_news-memory:chrome:all_processes:reported_by_chrome:partition_alloc:effective_size_avg/load_news_wikipedia
Relative Change: 1.47%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/winx64ati_perf_bisect/builds/1491
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9005164539772690976


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5875417597083648

| 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!