Training pauses after leaving my computer idle for a while, but resumes after I move the mouse or keyboard

I’m training a simple network on a single GPU overnight, however I notice that the training would stop after an hour or so and would continue when I move the mouse or keyboard (attached screenshot, the training pauses at epoch 76 and resumes after I moved the mouse).

So last night I decided to run a separate timing script (attached below) whilst training the network to check whether this is a PyTorch problem or something else, the training ran without any problem.

# timing script
from datetime import datetime
import time

while(1):
    now = datetime.now()
    current_time = now.strftime("%H:%M:%S")
    print("Current Time =", current_time)
    time.sleep(300)

Maybe your system is configured to shut down the GPU or your overall system if no user input is noticed. PyTorch itself won’t just pause your training.