1320148 - [meta] Toolbox startup performance

Status: RESOLVED DUPLICATE of bug 1320786

(DevTools :: General, defect, P3)

Description

[Alexandre Poirot [:ochameau]]

Just some random numbers about toolbox startup performances as I'm not sure we recently looked at it.

As of today, 21 modules are loaded during firefox startup.

331 modules to load to open the toolbox with the inspector.
  3.2, 4.3, 4.0s to load against about:blank
  0.8, 1.1, 0.9s just for gcli
392 modules with the console.
  2.8, 2.9, 2.7s to load against about:blank
  1.5, 1.3, 1.2s just for gcli
250 modules with the debugger.
  3.4, 3.6, 4.7s to load against about:blank
  0.8, 0.9, 1.0s just for gcli

Obviously module loading is an important cost center.
I quickly identified gcli as a performance issue by using the profiler and it is mosly because of it loading zillions of modules (about 64).

I measure the time to load a toolbox by looking at how much times gDevTools.showToolbox takes to resolves its promise, which is resolved when the tool's Panel.open resolves.
I probe gcli setup within toolbox.js in Toolbox._buildButtons where we call createRequisition, getCommandBarSpec and createButtons.

I would like to keep this bug as a meta bug for frontend performances, where we could study where are the existing slowness and open specific bugs once we identified something that could be tuned.

Comment 1

[Alexandre Poirot [:ochameau]]

Attachment: Dump toolbox+gcli load time.

Here is how I logged the load times.

Comment 2

[Alexandre Poirot [:ochameau]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=0026fd514e8b

Comment 3

[Alexandre Poirot [:ochameau]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=73be6f504dc9

Comment 4

[Alexandre Poirot [:ochameau]]

I forgot about this bug while filling bug 1320786... I'm going to use the newest.