ARSD PNG memory usage

[Joerg Joergonson via Digitalmars-d-learn]

> The CPU usage is consistently very low on my computer. I still 
> don't know what could be causing it for you, but maybe it is 
> the temporary garbage... let us know if the new patches make a 
> difference there.
>

Ok, I tried the breaking at random method and I always ended up 
in system code and no stack trace to... seems it was an alternate 
thread(maybe GC?). I did a sampling profile and got this:

Function Name	Inclusive  Exclusive Inclusive % Exclusive %
_DispatchMessageW at 4	10,361	5	88.32	0.04
[nvoglv32.dll]   	7,874	745	67.12	6.35
_GetExitCodeThread at 8	5,745	5,745	48.97	48.97
_SwitchToThread at 0	2,166	2,166	18.46	18.46

So possibly it is simply my system and graphics card. For some 
reason NVidia might be using a lot of cpu here for no apparent 
reason?

DispatchMessage is still taking quite a bit of that though?


Seems like someone else has a similar issue:

https://devtalk.nvidia.com/default/topic/832506/opengl/nvoglv32-consuming-a-ton-of-cpu/


https://github.com/mpv-player/mpv/issues/152


BTW, trying sleep in the MSG loop

Error: undefined identifier 'sleep', did you mean function 
'Sleep'?		

"import core.thread; sleep(10);"

;)

Adding a Sleep(10); to the loop dropped the cpu usage down to 
0-1% cpu!

http://stackoverflow.com/questions/33948837/win32-application-with-high-cpu-usage/33948865

Not sure if that's the best approach though but it does work.

They mention to use PeekMessage and I don't see you doing that, 
not sure if it would change things though?