All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=771313

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=c836d43c76e9cd251fe0113439b0bcbc6007040eb7e4cead596e307d16fdfe7e


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

chromium-rel-mac-retina

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8966725421072977440

Looking at the graph I feel the alert should have actually been on 504538. If bisect fails to return any result we should do that and retry.

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

Bisect Details
  Configuration: mac_retina_perf_bisect
  Benchmark    : system_health.common_desktop
  Metric       : cpu_time_percentage_avg/browse_search/browse_search_google

Revision             Result                      N
chromium@504916      0.180565 +- 0.0341955       21      good
chromium@504971      0.183437 +- 0.00822499      21      bad

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.search.google system_health.common_desktop

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8966725421072977440


For feedback, file a bug with component Speed>Bisection

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8966194308574935616

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

Bisect Details
  Configuration: mac_retina_perf_bisect
  Benchmark    : system_health.common_desktop
  Metric       : cpu_time_percentage_avg/browse_news/browse_news_flipboard

Revision             Result                     N
chromium@504459      0.328429 +- 0.0166027      21      good
chromium@504538      0.330089 +- 0.0186582      21      bad

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.news.flipboard system_health.common_desktop

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8966194308574935616


For feedback, file a bug with component Speed>Bisection

Closing this as WontFix. Unfortunately, as long as system_health doesn't have a reference build, it's impossible to tell whether this is a real regression or due to environmental factors.