All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=646828

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgmcq-qwoM


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

android-nexus7v2

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9001540523984414848

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


===== TESTED REVISIONS =====
Revision         Mean     Std Dev  N   Good?
chromium@416493  4880501  241120   12  good
chromium@416715  4607978  113133   5   good
chromium@416716  4653907  95337.9  5   good
chromium@416717  5137429  58604.2  5   bad
chromium@416719  5020693  50772.7  5   bad
chromium@416722  5134238  87921.5  5   bad
chromium@416729  5086847  69948.9  5   bad
chromium@416743  5103855  45152.8  5   bad
chromium@416771  5098635  57884.2  5   bad
chromium@416826  5082517  64774.5  5   bad
chromium@416937  5099557  60581.8  18  bad

Bisect job ran on: android_nexus7_perf_bisect
Bug ID: 646828

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --also-run-disabled-tests memory.long_running_idle_gmail_tbmv2
Test Metric: memory:chrome:renderer_processes:reported_by_chrome:v8:heap:map_space:effective_size_avg/memory:chrome:renderer_processes:reported_by_chrome:v8:heap:map_space:effective_size_avg
Relative Change: 5.26%
Score: 0

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus7_perf_bisect/builds/3311
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9001540523984414848


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=6434088594964480

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Most likely caused by https://chromium.googlesource.com/v8/v8/+/eca8a5ebbdab6b3276fca3abead893fd721336a0

It did not affect total heap size, only the map size.