1442827 - Add instrumentation to collect XBL used on the startup path

Status: RESOLVED WONTFIX

(Core :: DOM: Core & HTML, task, P5)

Description

[Zibi Braniecki [:zbraniecki][:gandalf]]

As a follow-up to bug 1426509 it would be useful to collect information on what XBL bindings are used on the startup path.

That would make allow us to target them and prioritize removal of XBL bindings from the startup path.

Comment 1

[Dave Townsend [:mossop]]

When do we define startup as complete? When the main browser windows have finished restoring?

Comment 2

[Brian Grinstead [:bgrins]]

(In reply to Dave Townsend [:mossop] from comment #1)
> When do we define startup as complete? When the main browser windows have
> finished restoring?

Forwarding question to Florian

Comment 3

[Florian Quèze [:florian]]

(In reply to Dave Townsend [:mossop] from comment #1)
> When do we define startup as complete? When the main browser windows have
> finished restoring?

There are several possible answers:
1. when we have painted a first browser window (ie. after the first "browser-delayed-startup-finished" notification)
2. when we are done with session restore (ie. after "sessionstore-windows-restored")
3. when we are first idle after finishing everything (ie. after "sessionstore-windows-restored" + several idle callbacks, eg. https://searchfox.org/mozilla-central/rev/78dbe34925f04975f16cb9a5d4938be714d41897/browser/components/tests/startupRecorder.js#128-136)

If it's reasonable to assume that the XBL bindings will be the same in all browser windows, and that you don't care about stuff done by add-ons soon after first paint, then #1 is enough.

Comment 4

[alexander :surkov (:asurkov)]

I suppose this one can be closed safely now: a few bindings are left only, so there's nothing to prioritize now.