1355053 - 0.52 - 0.52% compiler_metrics num_static_constructors (linux32, linux64-stylo) regression on push 40479d157fc874df89dd7b7f959f761319aece49 (Wed Mar 15 2017)

Status: RESOLVED WORKSFORME

(Core :: Panning and Zooming, defect)

Description

[Ionuț Goldan [:igoldan]]

We have detected a build metrics regression from push 40479d157fc874df89dd7b7f959f761319aece49. As author of one of the patches included in that push, we need your help to address this regression.

Regressions:

  1%  compiler_metrics num_static_constructors linux64-stylo debug      191 -> 192
  1%  compiler_metrics num_static_constructors linux32 debug            191 -> 192


You can find links to graphs and comparison views for each of the above tests at: https://treeherder.mozilla.org/perf.html#/alerts?id=5465

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 jobs in a pushlog format.

To learn more about the regressing test(s), please see: https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Automated_Performance_Testing_and_Sheriffing/Build_Metrics

Comment 1

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

as a note, we recently shifted our threshold to be last least 3 num_static_constructors to generate an alert, please use this as good information, but maybe not a requirement to do anything.

Comment 2

[Kartikaya Gupta (email:[e-mail])]

Is there a way for me to reproduce this locally or on try? (i.e. some way for me to generate the number of constructors). I suspect it's counting [1] as a static constructor but I'd want to modify the line to make sure.

[1] https://hg.mozilla.org/mozilla-central/rev/8dcb0cd0ee36#l4.15

Comment 3

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

redirecting to :froydnj, he is the oracle of static constructors :)

Comment 4

[Nathan Froyd [:froydnj]]

Ah, your patch added a new .cpp, so what likely happened is that the particular files in two unified build files got shifted around a bit, and one of those files that didn't have a static constructor previously now does.  I don't think you have anything to worry about here.

Comment 5

[Kartikaya Gupta (email:[e-mail])]

Ah, thanks!