All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=764343

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=923c88332e582a55b332ea58c0d8086e203788980c82a9b473d04cc1ac5f0ca2


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

chromium-rel-win7-gpu-intel

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8968648642898391920

=== BISECT JOB RESULTS ===
NO Perf regression found

Bisect Details
  Configuration: winx64intel_perf_bisect
  Benchmark    : loading.desktop
  Metric       : cpuTimeToFirstMeaningfulPaint_avg/pcv1-warm/Mercadolivre

Revision             Result                  N
chromium@500376      86.1377 +- 28.7219      21      good
chromium@500474      84.2921 +- 28.1096      21      bad

To Run This Test
  src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=Mercadolivre loading.desktop

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8968648642898391920


For feedback, file a bug with component Speed>Bisection

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8965301362976235760

Bisecting on a wider range.

 Issue 764342  has been merged into this issue.

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

Hi xunjieli@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 : xunjieli
  Commit : 724bb776bcdea642a5bc9cc20fe14bb0282b4900
  Date   : Wed Sep 06 14:29:20 2017
  Subject: [Telemetry] Use --ignore-certificate-errors-spki-list to bypass cert errors

Bisect Details
  Configuration: win_x64_perf_bisect
  Benchmark    : loading.desktop
  Metric       : cpuTimeToFirstMeaningfulPaint_avg/pcv1-warm/Mercadolivre
  Change       : 18.98% | 88.6862142857 -> 105.518142857

Revision                                 Result                  N
chromium@500264                          88.6862 +- 7.99407      14      good
chromium@500341                          89.5953 +- 2.48104      6       good
chromium@500344                          89.9207 +- 3.81362      6       good
chromium@500344,catapult@c5a474f50f      88.992 +- 2.87489       6       good
chromium@500344,catapult@724bb776bc      113.295 +- 14.3343      6       bad       <--
chromium@500344,catapult@80c47581b1      101.424 +- 19.9661      6       bad
chromium@500344,catapult@4f611510b9      108.429 +- 19.4748      6       bad
chromium@500344,catapult@442f46edf7      104.295 +- 19.8032      6       bad
chromium@500345                          107.234 +- 16.6696      6       bad
chromium@500346                          106.81 +- 23.6971       6       bad
chromium@500351                          107.651 +- 14.818       6       bad
chromium@500361                          103.941 +- 18.8473      6       bad
chromium@500380                          101.36 +- 20.5327       6       bad
chromium@500418                          106.613 +- 5.62508      6       bad
chromium@500572                          105.518 +- 72.4144      14      bad

To Run This Test
  src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=Mercadolivre loading.desktop

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8965301362976235760


For feedback, file a bug with component Speed>Bisection

cpuTimeToFirstMeaningfulPaint_avg increased for Mercadolivre site. 
https://chromeperf.appspot.com/report?sid=00e5177dc24fbe19cdeb0c654702f83676f4f769fe67bf39130ac89bab04983d&start_rev=498039&end_rev=502757

The increase seems small and should not be a concern.
I will mark this as WontFix as this is an infra change and not a real regression.