Just to clarify, a single of the 4 cores is one third used (sometimes more), not all the CPU on the pi3.
My question is to establish whether this CPU usage is normal to maintain the display.
Just playing around with my Tingbot.
When it's showing the apps which can be selected, and the 'shoutout' app is ready to be selected but not yet running, my pi3's CPU is about 1/3 used.
Running strace on the Python which runs that application selector, it's repeatedly calling stat against the icon files, amongst other things.
Does the screen require the image to be repeatedly refreshed - is this how these touchscreens work?
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