1304628 - 2.12 - 3.61% sessionrestore / sessionrestore_no_auto_restore / tpaint / ts_paint (linux64, osx-10-10, windows7-32, windowsxp) regression on push a03e56efce4cc941844a5d1da71d8c1d5598e9b4 (Thu Sep 22 2016)

Status: RESOLVED FIXED

(Firefox :: Untriaged, defect)

Description

[Alison Shiue]

Talos has detected a Firefox performance regression from push a03e56efce4cc941844a5d1da71d8c1d5598e9b4. As author of one of the patches included in that push, we need your help to address this regression.

Regressions:

  4%  sessionrestore windows7-32 opt                        947.92 -> 982.17
  4%  sessionrestore_no_auto_restore windows7-32 opt        1003.88 -> 1039.17
  3%  ts_paint windows7-32 opt                              1018.75 -> 1048.5
  3%  sessionrestore linux64 opt                            1082.08 -> 1113.42
  3%  sessionrestore_no_auto_restore osx-10-10 opt          1092.62 -> 1122.33
  3%  sessionrestore osx-10-10 opt                          1048.38 -> 1075.08
  3%  sessionrestore windowsxp opt e10s                     769.5 -> 789
  2%  sessionrestore_no_auto_restore windowsxp opt e10s     803.42 -> 823.42
  2%  ts_paint windowsxp opt e10s                           946.17 -> 969.42
  2%  ts_paint osx-10-10 opt                                1135.21 -> 1162.33
  2%  ts_paint linux64 opt                                  1616.12 -> 1654.75
  2%  tpaint windows7-32 opt                                305.86 -> 312.58
  2%  sessionrestore_no_auto_restore linux64 opt            1144.83 -> 1169.08


You can find links to graphs and comparison views for each of the above tests at: https://treeherder.mozilla.org/perf.html#/alerts?id=3334

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]

After doing some retriggers, this issue might be caused by one of the following patches:
https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=6a41bd18fe6c1417cb7683bd6dbdf474b15b97b0&tochange=a03e56efce4cc941844a5d1da71d8c1d5598e9b4

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

Comment 2

[Hannes Verschore [:h4writer]]

These commits have been backed out. The regression should be gone now.

Comment 3

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

ok, I see these backed out on the perfherder graphs.  :h4writer, do you want to leave this open to track the work for next time you land?  This seems to affect startup tests across the board.

Comment 4

[Hannes Verschore [:h4writer]]

Not really. But please open a new bug if it comes back. I'm not entirely sure which patch caused it. I have an idea but I could be wrong.

Comment 5

[Julien Cristau [:jcristau]]

updating 52 status flag, since this was backed out.