1466927 - The page at https://androidify.com/en/#/create takes a very long time to load with the profiler enabled

Status: NEW

(Core :: Gecko Profiler, defect, P2)

Description

[Mike Conley (:mconley) (:⚙️) (PTO Dec 22 - Jan 2)]

STR:

1. Enable the Gecko Profiler
2. Load https://androidify.com/en/#/create

ER:

Page should finish loading within a reasonable amount of time.

AR:

Page seems to take a long time to load.

Here's a profile:

https://perf-html.io/from-addon/calltree/?hiddenThreads=0-1-2-3-4-5-6-8-9-10-11-12-13-14-15-16-17-18-19-20-21-22-23-24-25-26-27-28-29-30&range=6.1970_11.8469&thread=7&threadOrder=0-1-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18-19-20-21-22-23-24-25-26-27-28-29-30-2&v=3

I thought this sounded a lot like bug 1145297, but looking at the profile, it doesn't look like the same underlying cause.

Comment 1

[Daniel Holbert [:dholbert]]

(In reply to Mike Conley (:mconley) (:⚙️) (Catching up on needinfos / reviews) from comment #0)
> https://perf-html.io/from-addon/[...]

(Looks like this wasn't a profile that got uploaded -- it was just the local addon view.  Mind recapturing & clicking the share button?)

Comment 2

[Mike Conley (:mconley) (:⚙️) (PTO Dec 22 - Jan 2)]

Whoops - sorry. Here we are: https://perfht.ml/2sIBqs1

Comment 3

[Julien Wajsberg [:julienw]]

Attachment: app.js

This is the prettified JS file that's loaded in this page.

Filtering by JS implementation we can see a very significant part of the profile is spent in this JS script at the root scope.

When moving back to the "combined" filter, we see this time is especially composed of:
* NewArrayOperation
* DefineDataElement

Looking at the JS file, a very significant part of it is about instanciating "o.Animation" objects with big objects as parameters. I'm not sure whether that's done at load time, but I think it is.

Comment 4

[Greg Tatum [:gregtatum]]

I can reproduce, and it does so only if profiling the GeckoMain thread, when I took out GeckoMain, but included other threads, it would not reproduce.

https://perfht.ml/2JRiCgE