All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=795780

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=589cd38a281acfa40d4ebf3a5edf5f16f3e7bdb931376c536ab20429c7dd0b70


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

linux-release

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/168a4dc6040000

📍 Couldn't reproduce a difference.
https://pinpoint-dot-chromeperf.appspot.com/job/168a4dc6040000

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/16f441a6040000

📍 Found a significant difference after 1 commit.
https://pinpoint-dot-chromeperf.appspot.com/job/16f441a6040000

Statically link fontconfig on Linux
By thomasanderson@chromium.org · Fri Dec 15 15:53:31 2017
chromium @ 4f1a60552748d150783655ee6f7b6f7084e3af95

Understanding performance regressions:
  http://g.co/ChromePerformanceRegressions

+sullivan@ addressing_performance_regressions.md says that the bisect bot should have posted a message on this bug with instructions on how to reproduce the test, but it's missing in this case.  Which test do I need to run?

I think the documentation is stale and should be updated.

Meanwhile, the pinpoint job (https://pinpoint-dot-chromeperf.appspot.com/job/16f441a6040000) has this information about the failure:

benchmark: system_health.common_desktop
story: browse.search.google.india
configuration: linux-release

To run the test locally, use:

src/tools/perf/run_benchmark -v --browser=release --output-format=html --pageset-repeat=1 --also-run-disabled-tests --story-filter=browse.search.google.india system_health.common_desktop --output-dir=<SOME DIR>

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/15df5476040000

Thanks chiniforooshan@.  I ran the tests locally and got the attached results.  Runs 2 and 3 are without the CL, and 4 and 5 are with the CL applied.  I don't see a significant difference in the timings though.

Deleted: results.tar.gz 8.1 MB

results.tar.gz 8.1 MB Download

📍 Found a significant difference after 1 commit.
https://pinpoint-dot-chromeperf.appspot.com/job/15df5476040000

Statically link fontconfig on Linux
By thomasanderson@chromium.org · Fri Dec 15 15:53:31 2017
chromium @ 4f1a60552748d150783655ee6f7b6f7084e3af95

Understanding performance regressions:
  http://g.co/ChromePerformanceRegressions

Oh, sorry. If you want to try with local changes, instead of --browser=release please use --browser=exact --browser-executable=<path to your locally built chrome binary>.

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/14fc9d31040000

📍 Found a significant difference after 1 commit.
https://pinpoint-dot-chromeperf.appspot.com/job/14fc9d31040000

Roll HarfBuzz to 1.7.3 plus hb_set fix
By drott@chromium.org · Wed Dec 20 13:26:18 2017
chromium @ a14e00ae9bc6a9263bbfb249ec51b4ed6a7635c1

Understanding performance regressions:
  http://g.co/ChromePerformanceRegressions

Looks like things went back to normal after the harfbuzz roll (also the CL was reverted before the hb roll, but pinpoint didn't identify that as the source of the speedup)