958663 - [keyboard refactor] improve keyboard cold start time

Status: RESOLVED INVALID

(Firefox OS Graveyard :: Gaia::Keyboard, defect)

Description

[David Flanagan [:djf]]

In the past the keyboard was loaded with the system app at boot time. This is changing so that the app does not load until it is first used.  Therefore, the keyboard needs to be optimized for rapid startup.

We want the user to see a keyboard on screen quickly, even if the keyboard is not completely functional when it first appears.

This means that we need to render the keyboard first and get it displayed before querying settings. Optional features like the autocorrect engine should be loaded dynamically after the keyboard is rendered.

I think that it is the inital call to window.resizeTo() that triggers the animation of the keyboard sliding in. If we can know the size of the keyboard in advance (and I think we can) then maybe we should call resizeTo() first and then render the keyboard while the animation is occurring.  If that works and looks good, it could make things faster.

Dynamically loading JSON files for keyboard layouts might be a performance hit as well. Since these are quite small, we might want to include them directly in the app at build time so that a separate load step is not needed.  At least for the most commonly used layouts.  We'll have to measure.

Comment 1

[Rudy Lu [:rudyl] (inactive after 2015/7/3)]

Here is my testing branch to look into this issue,
https://github.com/RudyLu/gaia/tree/test_new_keyboard_loading

From my test, it took about 1.6s for keyboard frame to get mozbrowserloadend event after these steps:

 1. adb shell kill [Demo-keyboard PID]
 2. click an input field to re-launch the demo keyboard.
 3. See the logs

Comment 2

[Jan Jongboom [:janjongboom] (inactive)]

This'll be a lot less of an issue when bug 992346 lands.

Comment 3

[Rudy Lu [:rudyl] (inactive after 2015/7/3)]

Close this bug as we no longer work on the bugs under bug 956169.