DisplayingABitmap example consumes ~10% cpu

#1

Even an empty openfl project consumes ~10% of cpu on Desktop platform. Is there anything that can be done?
OSX i5 2.6Ghz

#2

What if you lower the FPS to 30, or enable vsync? Any changes?

#3

No effect. Cpu load does not changed. I compile it in release mode.

#4

Is this to C++, or to Neko? Does building with -Dcairo have an effect?

#5

C++, no effect.
I’ve checked in Instruments what is going on, here is a screenshot:
http://oi67.tinypic.com/mn0pwo.jpg

#6

We would probably need a debug build to understand how the CPU time is being used, but for reference, on my ThinkPad I get 0.3% CPU on “DisplayingABitmap” and 2.0% CPU when adding -Dcairo (which triggers software rendering)

I wonder if OpenGL is being used? You can use this to know what’s in use:

trace (stage.window.renderer.type);
#7

Without -Dcairo i got “OPENGL”

Is there any way to “sleep” rendering thread?

#8

It looks like macOS forces vsync, interesting

#9

In NME i got ~2.5% CPU usage for the same sample.
In XCODE Instruments you can see that lime.ndll causes this. ~10 functions are responsible for CPU usage.
50% is caused by:
_nextEventMatchingEventMask:untilDate:inMode:dequeue:]

#10

This seems to help on macOS here:

Are you able to build from source?

#11

Great !!!
It helped, now there is ~2.5-3.5% on mac.
I do not know if more optimizations are possible, but:

reason of 55%:
https://s11.postimg.org/fhk6pmdwx/Zrzut_ekranu_2016_10_12_o_06_13_47.png

reason of 24%:
https://s11.postimg.org/v4bg2zroz/Zrzut_ekranu_2016_10_12_o_06_12_30.png

reason of 16%:
https://s10.postimg.org/su6xdnhe1/Zrzut_ekranu_2016_10_12_o_06_19_08.png