After Arduino 1.6.7, Arduino LLC adds a new feature that can automatically plot the data from Serial using CSV format, so after finishing the hardware, the first test is using Serial plotter to check the data, and the first thing to test is my brand new Raspberry Pi 3, I'm quite curious about the wifi power peak looks like.

and this is the result

as you can see, the peak is about 400mA,but because of the limit of Serial plotter, I can't measure how long it takes to transmit wifi signal.

I've also tested current under CPU stress test, using sysbench.

not sure why there is a peak to 800mA.