Overhead, that’s the amount of power that’s needed to bring the hardware up to be able to do your work as well as put it back to sleep.
And overhead is the energy that is required to bring up the radios and all the other system hardware which is required for your application to perform work.
A case about considering that your application is also utilizing the networking component. Networking is going to bring up the radios which will require power for prolonged periods. So in this case you can try to optimize your networking utilization. Try to batch up all your networking activity within your application whenever possible so that it reduces the impact on the networking as well as the corresponding overhead which has resulted from it.
From WWDC’s script https://developer.apple.com/videos/play/wwdc2017/238/
just search the key word “Overhead”
