Python / CMD's Idle Usage

[Rachelnowhere]

When running the .bat file the cmd line opens and loads the Automatic1111 program. The GPU will sit at 3.3GB / 8GB, and it will remain at that amount of usage until the first render of an image (I usually just run a simple txt2img prompt just to get the code moving, otherwise the img2img doesn't work).
After the first render the GPU usage drops to 1.5GB / 8GB.
When closing the CMD window it drops to the usual idle of 0.5GB / 8GB.

So I guess me question is... why is this happening? If the code is just idling and not running any scripts... why is it draining 1GB of the GPU? Why is it sitting at 3.3GB until the first txt2img function is used?

I've noticed in the past that some Controlnet functions can take up to 15/20minutes to complete. But every now and then that will change. I was using the Reference function in Controlnet and it was completing the images at a max of 4mins. Then, I swapped the Reference image for another one and suddenly I was back to a 15/20min wait time. The only option changed out of everything was the Reference image in Controlnet. No prompts or sliders or anything else was touched.

Is the CMD window running a constant code while idling? What's going on here?