1499383 - 2.1 - 11.63% sessionrestore / sessionrestore_no_auto_restore (linux64, linux64-qr, windows10-64, windows10-64-qr, windows7-32) regression on push 0bf7bb3f9e581ee5da934136e404d794a130fddc (Mon Oct 15 2018)

Status: RESOLVED WONTFIX

(Firefox :: Screenshots, defect)

Description

[Ionuț Goldan [:igoldan]]

Talos has detected a Firefox performance regression from push:

https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=e18f1acd0782f6333ee892c7ebc9711d9a5e550a&tochange=0bf7bb3f9e581ee5da934136e404d794a130fddc

As author of one of the patches included in that push, we need your help to address this regression.

Regressions:

 12%  sessionrestore linux64 pgo e10s stylo                             313.92 -> 350.42
 11%  sessionrestore linux64 opt e10s stylo                             339.00 -> 376.58
 10%  sessionrestore_no_auto_restore linux64 opt e10s stylo             356.17 -> 392.75
  9%  sessionrestore_no_auto_restore linux64 pgo e10s stylo             335.25 -> 367.00
  7%  sessionrestore windows10-64 opt e10s stylo                        327.08 -> 350.67
  6%  sessionrestore_no_auto_restore windows10-64 opt e10s stylo        349.42 -> 369.75
  5%  sessionrestore windows10-64-qr opt e10s stylo                     337.67 -> 356.00
  5%  sessionrestore windows7-32 opt e10s stylo                         329.50 -> 347.08
  5%  sessionrestore_no_auto_restore windows10-64-qr opt e10s stylo     357.75 -> 376.83
  5%  sessionrestore_no_auto_restore windows7-32 opt e10s stylo         349.08 -> 366.25
  2%  sessionrestore linux64-qr opt e10s stylo                          823.17 -> 843.00
  2%  sessionrestore_no_auto_restore linux64-qr opt e10s stylo          842.00 -> 859.67


You can find links to graphs and comparison views for each of the above tests at: https://treeherder.mozilla.org/perf.html#/alerts?id=16835

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

[Andrew Swan [:aswan]]

Bug 1498027 may be related, you could try grabbing the proof-of-concept patch from that bug and seeing how much of the regression is eliminated by a run with it applied.

Comment 2

[Jared Hirsch [:jhirsch] (he/him) (Needinfo please)]

These regressions have been previously discussed and provisionally accepted by the addons team, see ddurst's comment here https://bugzilla.mozilla.org/show_bug.cgi?id=1491997#c14.