How to Read JavaFX Pulse Log Message

[Tai Hu]

Hi,
    Is there any document or tutorial about how to interpret JavaFX Pulse log message? I turned on Pulse Logger for my application and see the log message as follows,

PULSE: 575 [143ms:20ms]
T12 (-143 +143ms): Layout Pass
T12 (0 +0ms): CSS Pass
T12 (1 +0ms): Layout Pass
T12 (1 +0ms): Update bounds
T12 (1 +0ms): Waiting for previous rendering
T12 (1 +0ms): Copy state to render graph
T12 (2 +0ms): CSS Pass
T12 (3 +1ms): Layout Pass
T12 (4 +0ms): Update bounds
T12 (5 +0ms): Waiting for previous rendering
T12 (5 +2ms): Copy state to render graph
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 (8 +5ms): Painting
T9 (13 +1ms): Presenting
T9 (14 +0ms): Dirty Opts Computed
T9 : Slow shape path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 : Slow background path for null
T9 (14 +5ms): Painting
T9 (19 +0ms): Presenting
Counters:
	Cached region shape image used: 3
	NGRegion renderBackgroundShape slow path: 1
	NGRegion renderBackgrounds slow path: 26
	Nodes rendered: 212
	Nodes visited during render: 227

There is a lot of "Slow background path for null”. Is that indicating a problem? If so, how can I fix it?

Thanks,

Tai