All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=776738

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=775a4f37042af32d67983cbb500f07a5d3a04a7c5824b4862dc1bfe93cf72225


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

chromium-rel-mac12
chromium-rel-win10

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8965206933807464848

=== BISECT JOB RESULTS ===
Perf regression found with culprit

Suspected Commit
  Author : Stephen Chenney
  Commit : 8ff2371257ac4f24d77da4a62569840a53c49b47
  Date   : Thu Oct 12 13:11:52 2017
  Subject: Prevent squashing of border-radius layers

Bisect Details
  Configuration: mac_10_12_perf_bisect
  Benchmark    : system_health.memory_desktop
  Metric       : memory:chrome:all_processes:reported_by_chrome:gpu:effective_size_avg/browse_media/browse_media_tumblr
  Change       : 29.07% | 31462858.0 -> 40607802.0

Revision             Result                   N
chromium@508259      31462858 +- 2943610      6      good
chromium@508303      31578821 +- 2611697      6      good
chromium@508325      31922378 +- 3155325      6      good
chromium@508328      32587391 +- 3812179      6      good
chromium@508329      39738085 +- 2455098      6      bad       <--
chromium@508330      39800890 +- 5631578      6      bad
chromium@508331      40125839 +- 3887627      6      bad
chromium@508336      39810447 +- 3981424      6      bad
chromium@508346      40607802 +- 4443856      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=release --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=browse.media.tumblr system_health.memory_desktop

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8965206933807464848


For feedback, file a bug with component Speed>Bisection