All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=596841

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg4JebuAkM


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

chromium-rel-mac-retina

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

Hi ccameron@chromium.org, the bisect results pointed to your CL below as possibly
causing a regression. Please have a look at this info and see whether
your CL be related.


===== BISECT JOB RESULTS =====
Status: completed


===== SUSPECTED CL(s) =====
Subject : Disable CALayer overlays on 10.9
Author  : ccameron
Commit description:
  
This is causing issues with PDF and print-preview for yet-unknown
reasons. Hopefully we can re-enable CALayer overlays when we find the
fix.

BUG= 594343 

Review URL: https://codereview.chromium.org/1819193002

Cr-Commit-Position: refs/heads/master@{#382498}
Commit  : 52dd784270ee9386ceba4e29c198c86dea9912dc
Date    : Tue Mar 22 03:30:03 2016


===== TESTED REVISIONS =====
Revision                Mean Value  Std. Dev.   Num Values  Good?
chromium@382485         20.539395   0.191218    8           good
chromium@382493         20.485786   0.070621    5           good
chromium@382496         20.439561   0.048639    5           good
chromium@382497         20.431848   0.065241    5           good
chromium@382498         20.722653   0.054211    5           bad
chromium@382504         20.705642   0.063676    8           bad

Bisect job ran on: mac_retina_perf_bisect
Bug ID: 596841

Test Command: src/tools/perf/run_benchmark -v --browser=release --output-format=chartjson --also-run-disabled-tests smoothness.gpu_rasterization.tough_path_rendering_cases
Test Metric: frame_times/frame_times
Relative Change: 0.68%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/mac_retina_perf_bisect/builds/1225
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9017491510247373376


| 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 label Cr-Tests-AutoBisect.  Thank you!

===== BISECT JOB RESULTS =====
Status: completed


===== SUSPECTED CL(s) =====
Subject : Disable CALayer overlays on 10.9
Author  : ccameron
Commit description:
  
This is causing issues with PDF and print-preview for yet-unknown
reasons. Hopefully we can re-enable CALayer overlays when we find the
fix.

BUG= 594343 

Review URL: https://codereview.chromium.org/1819193002

Cr-Commit-Position: refs/heads/master@{#382498}
Commit  : 52dd784270ee9386ceba4e29c198c86dea9912dc
Date    : Tue Mar 22 03:30:03 2016


===== TESTED REVISIONS =====
Revision                Mean Value  Std. Dev.   Num Values  Good?
chromium@382450         20.507613   0.179459    8           good
chromium@382480         20.429345   0.023719    5           good
chromium@382493         20.410568   0.035727    5           good
chromium@382497         20.463723   0.058802    5           good
chromium@382498         20.711723   0.062544    5           bad
chromium@382499         20.65421    0.051067    5           bad
chromium@382501         20.662305   0.044928    5           bad
chromium@382508         20.692773   0.033051    8           bad

Bisect job ran on: mac_retina_perf_bisect
Bug ID: 596841

Test Command: src/tools/perf/run_benchmark -v --browser=release --output-format=chartjson --also-run-disabled-tests smoothness.gpu_rasterization.tough_path_rendering_cases
Test Metric: frame_times/frame_times
Relative Change: 0.77%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/mac_retina_perf_bisect/builds/1226
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9017491486405238448


| 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 label Cr-Tests-AutoBisect.  Thank you!

ccameron: is this worth following up on? Looks like it only showed up on the retina perfbot, and only a 0.7% regression, but does seem to be reproducible.

This patch turned out not to be necessary and has been reverted.