All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=651439

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg5a2K6goM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICglYjbugkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg5f3ltwoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICglbSnvAsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpdmF4QkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpdvLuQkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg5aC26gkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpYLu4gkM


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

chromium-rel-win10
chromium-rel-win7-dual
chromium-rel-win7-gpu-ati
chromium-rel-win7-gpu-intel
chromium-rel-win7-gpu-nvidia
chromium-rel-win7-x64-dual
chromium-rel-win8-dual
linux-release

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9000181305121967296

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

Hi dtapuska@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 : Move synthetic gesture input to be aligned with BeginFrame.
Author  : dtapuska
Commit description:
  
The timing of synthetic events seems almost random. It is best to align
it with something that doesn't fluctuate. Android already rAF aligns its
synthetic input so do this for aura and mac as well.

BUG= 646369 

Review-Url: https://codereview.chromium.org/2372873003
Cr-Commit-Position: refs/heads/master@{#421528}
Commit  : 5248d2a4cc2ac706f0404b6c6edf196f5b491539
Date    : Wed Sep 28 15:57:47 2016


===== TESTED REVISIONS =====
Revision         Mean       Std Dev      N  Good?
chromium@421521  0.0875378  0.000971553  5  good
chromium@421525  0.088837   0.0016134    5  good
chromium@421527  0.0879528  0.00342972   5  good
chromium@421528  0.223241   0.00266073   5  bad    <--
chromium@421534  0.224764   0.00302662   5  bad

Bisect job ran on: winx64_10_perf_bisect
Bug ID: 651439

Test Command: src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --also-run-disabled-tests scheduler.tough_scheduling_cases
Test Metric: queueing_durations/queueing_durations
Relative Change: 156.76%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/winx64_10_perf_bisect/builds/726
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9000181305121967296


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=6754103781228544

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tdresser, alexclarke, skyostil what are your opinions on this issue.

I definitely change the timing of the synthetic queuing of events in https://codereview.chromium.org/2372873003/

but the Mean changing isn't that substantial. It was 0.08ms before and now it is 0.22ms.

And this additional time is likely the generation of the synthetic input. Do you know how the queueing_duration is actual calculated?

This has now recovered.

I'm not sure it has recovered. It recovered because I reverted my change and then I relanded it yesterday and you can clearly see the graphs increase. But I think we are really talking about a small time here and that is the difference in how these queuing of synthetic input and main frame alignment works.