High CPU consumption even with auto_refresh=False

[monojk]

I noticed 100% CPU with my application on a Raspberry Pi, even I have several seconds sleep in my loop. I use auto_refresh = False

I can reproduce that behaviour with these modifications of examples/displayio_ssd1306_simpletest.py

from time import sleep
...
display = adafruit_displayio_ssd1306.SSD1306(display_bus, width=WIDTH, height=HEIGHT, auto_refresh=False)
...
display.auto_refresh = False        # just to be sure

while True:
    display.refresh()
    sleep(5)

How can I bring down the CPU usage?

[FoamyGuy]

I believe this is not specific to the SSD1306, but more generally with the way BlinkaDisplayIO works.

You can see this effect if you open a REPL and just import displayio while watching htop.

I'm not certain of all of the specifics but I think there is a background thread getting used during some part of the process for rendering that is running as soon as displayio gets imported.