All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=729007

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgut23qQsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-tT5vgkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDghoSXvQoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-rPqoQoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-pqs-AkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgurmfoQoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-oiMvQoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDguvnHrQsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-ujNrwsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDguqWPqgoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-resowoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgusa14QoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-oyhqQkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDguoG0gAgM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDguqLChwoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-pCG7gkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDguvfY_AoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-obK7goM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDg-uaGqAsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDgxo7ZqQsM


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

chromium-rel-mac-retina
chromium-rel-mac11
chromium-rel-mac11-pro
chromium-rel-win7-dual
chromium-rel-win7-gpu-ati
chromium-rel-win7-gpu-intel
chromium-rel-win7-gpu-nvidia

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8977894013780408960

=== BISECT JOB RESULTS ===
Bisect failed for unknown reasons

Please contact the team (see below) and report the error.


Bisect Details
  Configuration: winx64nvidia_perf_bisect
  Benchmark    : v8.runtimestats.browsing_desktop_classic
  Metric       : Optimize:duration_avg/browse_media/browse_media_youtube


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=browse.media.youtube v8.runtimestats.browsing_desktop_classic

Debug Info
  https://chromeperf.appspot.com/buildbucket_job_status/8977894013780408960

Is this bisect wrong?
  https://chromeperf.appspot.com/bad_bisect?try_job_id=6328861018554368


| O O | Visit http://www.chromium.org/developers/speed-infra/perf-bug-faq
|  X  | for more information addressing perf regression bugs. For feedback,
| / \ | file a bug with component Speed>Bisection.  Thank you!

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8977800841579079216

=== BISECT JOB RESULTS ===
Bisect failed for unknown reasons

Please contact the team (see below) and report the error.


Bisect Details
  Configuration: winx64nvidia_perf_bisect
  Benchmark    : v8.runtimestats.browsing_desktop_classic
  Metric       : Optimize:duration_avg/browse_media/browse_media_youtube


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=browse.media.youtube v8.runtimestats.browsing_desktop_classic

Debug Info
  https://chromeperf.appspot.com/buildbucket_job_status/8977800841579079216

Is this bisect wrong?
  https://chromeperf.appspot.com/bad_bisect?try_job_id=6328861018554368


| O O | Visit http://www.chromium.org/developers/speed-infra/perf-bug-faq
|  X  | for more information addressing perf regression bugs. For feedback,
| / \ | file a bug with component Speed>Bisection.  Thank you!

As a guess from the CL range, it might be Benedikt's "Decrease code size multiplier to 24". In the global scheme of things, I am not sure this regression is worth investigating, but assigning to Benedikt for confirmation.

Quite possible, yes. It's a heuristic.