All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=651457

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg5cbJvgsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpdvLuQoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg5cSrvwsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpev_vAsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg5avquAoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpeqXhAgM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpYr8-goM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpcvmrAkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg5caHsQoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpbrltQkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpe-YqwkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpfqd5ggM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpbuEtQoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpYfJ9AgM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpev__AgM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg5aaQqAoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpd_GswoM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg5c3mpAkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgpau3oQsM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg5aC26goM


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

webrtc-linux-large-tests
webrtc-mac-large-tests
webrtc-win-large-tests

Performance regression from chromium roll 14409. 
Do you think you could have a look and verify if it is expected.

Ok will take a look. 
Don't see any obvious libvpx change in the roll that would cause this,
but will try to repro locally.

Couldn't find any obvious cuplrit in the libvpx roll.
As this seems to only affect vp9 under svc and screenshare mode
(which is not currently used), will mark it as won't fix.