All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=776384

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=404a6599d9ff6a05390c761f26e61b1256e4ed68b3f198ed92563a81f553c647


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

android-webview-nexus5X

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8965293436857349376

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

Hi ksakamoto@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 : Kunihiko Sakamoto
  Commit : 07ec68095dc07849019a7362ba6cc67625c95c0b
  Date   : Wed Oct 18 10:35:41 2017
  Subject: Simplify CSSFontFaceSource a bit

Bisect Details
  Configuration: android_webview_arm64_aosp_perf_bisect
  Benchmark    : system_health.memory_mobile
  Metric       : memory:webview:all_processes:reported_by_chrome:cc:effective_size_avg/load_news/load_news_cnn
  Change       : 63.42% | 16469668.0 -> 26914468.0

Revision             Result                    N
chromium@509707      16469668 +- 0.0           6      good
chromium@509720      16469668 +- 0.0           6      good
chromium@509727      16469668 +- 0.0           6      good
chromium@509729      16469668 +- 0.0           6      good
chromium@509730      29003428 +- 0.0           6      bad       <--
chromium@509733      26914468 +- 11441705      6      bad
chromium@509759      26914468 +- 11441705      6      bad

Please refer to the following doc on diagnosing memory regressions:
  https://chromium.googlesource.com/chromium/src/+/master/docs/memory-infra/memory_benchmarks.md

To Run This Test
  src/tools/perf/run_benchmark -v --browser=android-webview --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=load.news.cnn system_health.memory_mobile

More information on addressing performance regressions:
  http://g.co/ChromePerformanceRegressions

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8965293436857349376


For feedback, file a bug with component Speed>Bisection

My patch might have caused over-triggering of font invalidation. I'll make a fix.

 Issue 776761  has been merged into this issue.

 Issue 776926  has been merged into this issue.

Issue 776791 has been merged into this issue.

 Issue 776763  has been merged into this issue.

 Issue 777325  has been merged into this issue.

 Issue 777403  has been merged into this issue.

 Issue 777332  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/cdca7f33c3b9d7796a105a94b0cb5ad63d43af19

commit cdca7f33c3b9d7796a105a94b0cb5ad63d43af19
Author: Kunihiko Sakamoto <ksakamoto@chromium.org>
Date: Tue Oct 24 03:08:15 2017

Prevent over-triggering of font invalidation

FontSelector::FontFaceInvalidated() is expensive since it causes full
style recalculation. This patch lets RemoteFontFaceSource not to call
it when unnecessary (e.g. in the middle of FontFace construction).

This will hopefully fix memory regression by https://crrev.com/c/722141.

Bug:  776384 
Change-Id: I86a9b27be2fd65f51cc6057a7c897f588c4897ce
Reviewed-on: https://chromium-review.googlesource.com/730032
Reviewed-by: Takashi Toyoshima <toyoshim@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Kunihiko Sakamoto <ksakamoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#511024}
[modify] https://crrev.com/cdca7f33c3b9d7796a105a94b0cb5ad63d43af19/third_party/WebKit/Source/core/css/CSSFontFace.cpp
[modify] https://crrev.com/cdca7f33c3b9d7796a105a94b0cb5ad63d43af19/third_party/WebKit/Source/core/css/CSSFontFace.h
[modify] https://crrev.com/cdca7f33c3b9d7796a105a94b0cb5ad63d43af19/third_party/WebKit/Source/core/css/RemoteFontFaceSource.cpp

OK, regressions recovered.