All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=845125

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=46d9a4526bc699f367cbc872d7541b141a6b03bd036f0eb4294b83012e6624eb


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

perf-go-webview-phone

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8945918624557216000

=== Auto-CCing suspected CL author paulmiller@google.com ===

Hi paulmiller@google.com, 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 : Paul Miller
  Commit : a4c78341c85c19d71e2eab8a8ade5fd2728d2437
  Date   : Wed May 09 22:56:56 2018
  Subject: WebView: Prepare to enable variations, part 2

Bisect Details
  Configuration: go-webview-phone-perf-bisect
  Benchmark    : memory.top_10_mobile
  Metric       : memory:webview:all_processes:reported_by_os:system_memory:proportional_resident_size_avg/foreground/http_en_m_wikipedia_org_wiki_Science
  Change       : 1.25% | 86719518.6667 -> 85634078.6667

Revision                                       Result                  N
android-chrome@a03058257f                      86719519 +- 449620      6      good
android-chrome@6bb0def17f                      88080927 +- 424036      6      good
android-chrome@6bb0def17f,chromium@557336      87913332 +- 539361      6      good
android-chrome@6bb0def17f,chromium@557349      87452020 +- 631795      6      good
android-chrome@6bb0def17f,chromium@557356      87569439 +- 332646      6      good
android-chrome@6bb0def17f,chromium@557359      87209332 +- 375412      6      good
android-chrome@6bb0def17f,chromium@557361      87589236 +- 552842      6      good
android-chrome@6bb0def17f,chromium@557362      85662239 +- 393448      6      bad       <--
android-chrome@50de738d9d                      85000905 +- 299320      6      bad
android-chrome@5295e0a3e4                      84255433 +- 213950      6      bad
android-chrome@6e1102cf1c                      84519284 +- 187869      6      bad
android-chrome@159f504c2c                      84735007 +- 420436      6      bad
android-chrome@120ca38372                      85634079 +- 288335      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=http.en.m.wikipedia.org.wiki.Science memory.top_10_mobile

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8945918624557216000


For feedback, file a bug with component Speed>Bisection

Hmm.. this is interesting, your CL appears to have caused a significant *improvement* on PSS memory usage by *Chrome* (on Android Go devices).

Do you think Paul that is expected?

My mistake, the PSS improvements are on WebView, though. So this makes a bit more sense.

That commit enabled variations in WebView. It causes WebView start the webView_service process, which shares the same Java code as WebView, which might improve the PSS number. The net memory impact for the entire system should be negative, though, since we're using an additional process.