[Development] QML instantiation performance

[Juha Vuolle]

Hello,

> It appears that the QQuickValueTypeProvider instances are continuously
> recreated (spinning at 100% and locking the incubator thread, which the main
> thread is waiting on).  Lars or Simon, are you able to guess what might
> cause this issue?  The implementation of qmlClearTypeRegistrations seems
> fairly straightforward, but my memory of the complexities of value type
> providers is hazy.
>
> Juha, are you seeing this issue also, or do I just have a broken build
> somehow?

Yes happens here too with similar back traces and high CPU loads (5.3.1 fedora).

This reminds me of an open bug that I hit when trying to use incubators:
https://bugreports.qt-project.org/browse/QTBUG-36826
(I am not sure if Monsieur Alpert is actively looking at issues these days.)
In my application I've set some asynchronous loadings to false because
they hang occasionally.

cheers,
Juha