1700089 - Consider a lazy import of TelemetryController.jsm in CrashManager.jsm

Status: RESOLVED DUPLICATE of bug 1700079

(Toolkit :: Crash Reporting, enhancement)

Description

[Andrew Creskey [:acreskey]]

From startup profiling of Fenix on a MotoG5, we noticed that the biggest chunk of the crashManager import is spent importing TelemetryController.jsm
https://share.firefox.dev/3lwFxCb

Is it feasible to make the import of TelemetryController.jsm a lazy import, i.e. ChromeUtils.defineModuleGetter as in the following patch?
https://hg.mozilla.org/try/rev/641df798ce32a1bca1da6094b7d1f519c915af38

Comment 2

[Andrew Creskey [:acreskey]]

I did measure this change on Fenix (motoG5), via perftest startup.
I could not discern a measurable improvement.

However deferring the import, if it's possible, seems like its unequivocally better.

------------------
baseline
count    40.000000
mean   2376.475000
std      63.316457
min    2293.000000
10%    2317.700000
25%    2343.250000
50%    2362.500000
75%    2395.250000
90%    2428.100000
95%    2480.500000
max    2652.000000
------------------


------------------
test
count    40.000000
mean   2374.475000
std      48.839343
min    2320.000000
10%    2326.600000
25%    2342.750000
50%    2364.000000
75%    2393.750000
90%    2422.700000
95%    2445.700000
max    2583.000000
------------------