How do I find out why the render loop is running?

Kevin Rushforth kevin.rushforth at
Mon Sep 29 23:43:56 UTC 2014

I would suggest using the pulse logger, but it doesn't look like that 
logs the reason for a pulse. It will show renderer activity, though, 
which might be useful.

Typical reasons for a pulse to run are:

1) A an active Timeline or AnimationTimer

2) A control, such as a ProgressIndicator, that uses animation to 
display changes (even if the control is scrolled off the screen)

If the app is minimized (iconified) then the renderer shouldn't actually 
do anything though the pulse is running, but any animations will still run.

-- Kevin

Mike Hearn wrote:
> My app consistently uses about 10-15% of a CPU even when off screen and
> nothing is being animated. I had assumed JFX would idle in this case but it
> seems not. I suspect I've done something that is forcing the system to
> "pulse" no matter what, but I don't know where to begin investigating this.
> Profiling just shows lots of time being spent in quantum.

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