ICE can't full multi thread? (or am I forgot something?)

[opoppopopp]

I remenber this same sample scene can use all 4 thread on my good old AMD phenom 9550(win 7)
Just got this new machine(windows 10 with ryzen), Can't ICE utilize all thread? only 15%-30%
Or maybe only this scene, with some single thread bonded nodes cause that bottleneck?

rending no problem, btw.