All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=763773

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=668db8301d4ea76f7d072b19233ca5a9f981c234fcdd06ade514269a5aaad2bd


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

chromium-rel-mac11-pro
chromium-rel-win7-dual

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8968774068593926720

It's this one:  [parser] Tentatively enable FLAG_preparser_scope_analysis. by Marja Hölttä · 7 days ago

It's expected that the parsing work shifts a bit - the total parsing time should go down anyway.

cbruni@, the background parse time is properly included in the total parse time, right?

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

Suspected Commit
  Author : Marja Hölttä
  Commit : 36d703778ccd0d2777e0d4b69ed6e65e39a9f521
  Date   : Mon Sep 04 16:05:39 2017
  Subject: [parser] Tentatively enable FLAG_preparser_scope_analysis.

Bisect Details
  Configuration: win_perf_bisect
  Benchmark    : v8.runtimestats.browsing_desktop
  Metric       : Parse-Background:duration_avg/browse_news/browse_news_flipboard
  Change       : 43.26% | 58.4246666667 -> 83.7003333333

Revision                           Result                  N
chromium@499527                    58.4247 +- 5.95954      6      good
chromium@499534                    57.9582 +- 4.51026      6      good
chromium@499538                    58.8667 +- 4.687        9      good
chromium@499538,v8@1c1457fa70      58.4388 +- 5.37656      6      good
chromium@499538,v8@36d703778c      85.139 +- 7.28699       6      bad       <--
chromium@499538,v8@7abdadca0e      82.6257 +- 1.17896      6      bad
chromium@499539                    83.3813 +- 3.81709      6      bad
chromium@499540                    75.4346 +- 69.3439      9      bad
chromium@499541                    83.7003 +- 2.27287      6      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 v8.runtimestats.browsing_desktop

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8968774068593926720


For feedback, file a bug with component Speed>Bisection

There is a Group-Parse-Total and Group-Compile-Total category in our internal top25 benchmarks which I think don't appear on the telemetry-based version.

Currently you have to manually compare against Parse:duration_avg and get the delta:

https://chromeperf.appspot.com/report?3405=y&sid=9cac5ede51c7aa884534ed5c2caa62d1da244e5e182fb7b99840e3340919ebf2&start_rev=493985&end_rev=500815

I do not think manual comparison really scales for those 100 regressions that came out from this.

yeaaah probably not ;)

The overall regressions/improvements look okayish: https://chromeperf.appspot.com/group_report?rev=499541

The overall parse-total graph shows a positive result, Toon had a solution in mind to reduce the preparse-resolution time for functions without inner functions which should address some of the regressions we see. 

https://chromeperf.appspot.com/report?sid=55bf18a1005fdba7ad2b4b796d32b7f4f4823999d8a3e0619fef5a1b90e588b5&start_rev=47586&end_rev=47931

Parse time; 3 Regressions vs. 18 clear improvements (including speedometer):
- adwords: 12% slower
- facebook: 8% slower
- linkedin: 9% slower