I noticed that both the Mathematica front end and kernel are using the CPU constantly. In the end this hurts battery life and is particularly inconvenient when I forget to bring the charger to work ...
The kernel CPU usage hovers around 0.6% for both the main kernel and service kernel:
(A standalone kernel, i.e. one not connected to a front end, is using only 0.1%.)
The front end CPU usage hovers around 1.3%:
OS X always blames Mathematica for using a lot of power:
All this is with a freshly started Mathematica with a single empty notebook.
Most importantly, having Mathematica running in the background does have a noticeable effect on battery life, even after forcing the OS to use only integrated graphics. That's actually surprising because the CPU usage is really low. But why is it there at all? Other programs typically have 0% CPU usage when idle.
Is this normal or is there something broken on my system? Is it specific to OS X?
This is on OS X 10.11.6 with Mathematica 11.0.0, but it's been the same with earlier versions too as far as I remember.