1534210 - 47.01% sessionrestore_no_auto_restore (windows10-64-pgo-qr) regression on push a9bb4a23d4072a2735b50b577f9668728af06d30 (Mon Mar 4 2019)

Status: RESOLVED WONTFIX

(Testing :: Talos, defect)

Description

[Florin Strugariu [:Bebe]]

Talos has detected a Firefox performance regression from push:

https://hg.mozilla.org/integration/autoland/pushloghtml?changeset=a9bb4a23d4072a2735b50b577f9668728af06d30

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

Regressions:

47% sessionrestore_no_auto_restore windows10-64-pgo-qr opt e10s stylo 359.17 -> 528.00

You can find links to graphs and comparison views for each of the above tests at: https://treeherder.mozilla.org/perf.html#/alerts?id=19834

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/Performance_sheriffing/Talos/Tests

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

Comment 1

[Molly Howell (she/her) (no longer active)]

The bug 1510276 patch is in installer code, so unless the affected test is actually running the installer (and it doesn't look like it is?), there shouldn't be any relation to bug 1510276.

Comment 2

[Robert Strong (they/them - no direct email)]

Also...
the previous point on the graph for the alert has a date / time stamp of Sat Mar 02, 03:18:22.
the point on the graph for the alert has a date / time stamp of Mon Mar 04, 11:11:39.

So, besides this code not being executed via talos there are also 55 hours of landings between the known good and the known bad.

Comment 3

[Robert Strong (they/them - no direct email)]

I believe this covers the pushes to autoland during this time
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=4166cae81546f54accae807413f806d20bf30920&tochange=a9bb4a23d4072a2735b50b577f9668728af06d30

From that I suspect that bug 1531520 might have caused this.

Comment 4

[Robert Strong (they/them - no direct email)]

Talked with Felipe and he confirmed. The OS X version of this bug is bug 1532548 and this is wontfix for the same reason per Felipe.