Blender 2.8 CPU ressource usage

hi,

i am testing Blender 2.8. Everything is really nice and really some really good job has been done ! thanks a lot for that to all Blender contributors !

One thing i noticed is the CPU ressource is higher than 2.79.
I have run both 2.79 and 2.8 with same scene and similar configuration and 2.8 needs twice the CPU power ok the 2.79

For the record, i switched Blender 2.8 to Workbench rendering mode, but same as eevee

I am on a macbook pro 15" retina late 2013, core i7 2,3 GHz, 16 G RAM and GeForce GT 750M 2G RAM under macOS Mojave

for the record, in 2.79 CPU usage is 14%

see screen caps attached

thanks