1295490 - 2.87 - 8.29% damp (osx-10-10, windows7-32, windows8-64) regression on push 3d8a4df99f0ff5fab38afc6de0a678c043cf2ad4 (Thu Aug 11 2016)

Status: RESOLVED FIXED

(Firefox :: Untriaged, defect)

Description

[Alison Shiue]

Talos has detected a Firefox performance regression from push 3d8a4df99f0ff5fab38afc6de0a678c043cf2ad4. As author of one of the patches included in that push, we need your help to address this regression.

Summary of tests that regressed:

  damp summary windows7-32 opt e10s: 271.06 -> 280.13 (3.35% worse)
  damp summary osx-10-10 opt e10s: 268.98 -> 276.7 (2.87% worse)
  damp summary windows7-32 pgo e10s: 200.52 -> 211.7 (5.58% worse)
  damp summary windows8-64 opt e10s: 259.35 -> 280.86 (8.29% worse)


You can find links to graphs and comparison views for each of the above tests at: https://treeherder.mozilla.org/perf.html#/alerts?id=2485

On the page above you can see an alert for each affected platform as well as a link to a graph showing the history of scores for this test. There is also a link to a treeherder page showing the Talos jobs in a pushlog format.

To learn more about the regressing test(s), please see: https://wiki.mozilla.org/Buildbot/Talos/Tests

For information on reproducing and debugging the regression, either on try or locally, see: https://wiki.mozilla.org/Buildbot/Talos/Running

*** Please let us know your plans within 3 business days, or the offending patch(es) will be backed out! ***

Our wiki page outlines the common responses and expectations: https://wiki.mozilla.org/Buildbot/Talos/RegressionBugsHandling

Comment 1

[Alison Shiue]

This issue might be caused by one of following changesets: 
https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=c9879bf9369e8410c0e44d8ca35565b76c99e7e4&tochange=3d8a4df99f0ff5fab38afc6de0a678c043cf2ad4

Hi Jon, as you are the patch author, can you take a look at this and determine what is the root cause? Thanks!

Comment 2

[Jon Coppeard (:jonco)]

I've run the tests locally (on MacOS) before and after the changes, but I didn't see any significant differences.  Continuing to investigate.

Comment 3

[Jon Coppeard (:jonco)]

All of these tests seems to have returned to their original levels since the final backout of bug 1293239 on August 22nd.

Comment 4

[Joel Maher ( :jmaher ) (UTC -8)]

I see that, shall we marked this as resolved->fixed?

Comment 5

[Jon Coppeard (:jonco)]

Marking fixed.

Comment 6

[Gerry Chang [:gchang]]

Per comment #3 & 5, mark 51 as fixed.