1734134 - 0.16 - 0.14% installer size / installer size (OSX) regression on Thu September 30 2021

Status: RESOLVED WONTFIX

(DevTools :: Debugger, defect)

Description

[Andra Esanu (needinfo me)]

Perfherder has detected a build_metrics performance regression from push 9065e6be26ac940213bb3b984cc38471e11aa247. As author of one of the patches included in that push, we need your help to address this regression.

Regressions:

Ratio	Test	Platform	Options	Absolute values (old vs new)
0.16%	installer size	osx-shippable	nightly	83,298,576.29 -> 83,430,371.25
0.14%	installer size	osx-shippable	nightly	83,301,092.29 -> 83,420,749.00

Details of the alert can be found in the alert summary, including links to graphs and comparisons for each of the affected tests. Please follow our guide to handling regression bugs and let us know your plans within 3 business days, or the offending patch(es) will be backed out in accordance with our regression policy.

For more information on performance sheriffing please see our FAQ.

Comment 1

[Nicolas Chevobbe [:nchevobbe]]

In order to fix Bug 1730475, we had to update a third-party library (@babel/core), which I guess explains this bump.
Not sure we can do much about it except dropping babel and use Reflect instead (but I think Reflect is missing things that babel has, like getting an AST for an html source?)
Or we could try to tweak our webpack configuration to get smaller bundles.
bomsy, do you know if some work was done in this area in the past?

Comment 2

[Marco Castelluccio [:marco]]

Set release status flags based on info from the regressing bug 1730475

Comment 3

[Hubert Boma Manilla (:bomsy)]

Attachment: Bug 1734134 - [devtools] Uglify the bundled output to improve size r=nchevobbe

Comment 4

[Jan Honza Odvarko [:Honza] (always need-info? me)]

The installer size regression is caused by updating @babel/core, which we needed to support new Class Static Initialization Blocks (introduced in SM in this bug 1725689) in DevTools

We could uglify the JS, but that would make it hard to follow user bug reports with stack-traces.

Since the regression is relatively small I am closing this bug and leaving the size as is (I also checked with RyanVM offline about this)

Honza