All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=661925

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgo93rogkM


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

chromium-rel-win7-gpu-ati

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8997022614293043888

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


===== SUSPECTED CL(s) =====
Subject : [loading metric] filter out events during cache warming
Author  : ksakamoto
Commit description:
  
The regexp in prepareTelemetryInternalEventPredicate did not match
the titles of events logged by cache_temperature.py.

Note for perf sheriffs: Improvements are expected in page_cycler_v2
benchmarks.

BUG=catapult:#2962

Review-Url: https://codereview.chromium.org/2467763002
Commit  : 0d3575d73a471a53e1d1d363a349ad4536f293fc
Date    : Tue Nov 01 12:17:02 2016


===== TESTED REVISIONS =====
Revision                             Mean     Std Dev   N  Good?
chromium@428987                      1473.49  195.829   5  good
chromium@428992                      1404.57  134.056   5  good
chromium@428992,catapult@0d3575d73a  63.1824  1.50858   5  bad    <--
chromium@428993                      63.5284  1.72905   5  bad
chromium@428994                      62.2726  1.6931    5  bad
chromium@428995                      62.5732  0.619138  5  bad
chromium@428997                      62.7216  1.041     5  bad
chromium@429007                      62.4398  0.619536  5  bad

Bisect job ran on: winx64ati_perf_bisect
Bug ID: 661925

Test Command: src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests page_cycler_v2.typical_25
Test Metric: timeToFirstContentfulPaint_avg/pcv1-warm/http___colorado.edu
Relative Change: 95.76%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/winx64ati_perf_bisect/builds/1637
Job details: https://chromeperf.appspot.com/buildbucket_job_status/8997022614293043888


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  https://chromeperf.appspot.com/bad_bisect?try_job_id=5489650171379712

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This is expected, because now the page is very quickly loaded from cache (the value is close to zero, but not really zero). There was a bug that PCv2 recorded values from cache-warming page loads too.