When I do a render, for example with gpu acceleration, I see that samples per second increase gradually and then stop on a value (for example 1000).
So, I leave the computer and come back after a few hours: i find the screensaver (I have unchecked to stop the disks in mac preference), and i found indigo is going but I see that the samples per pixel restart at low values and gradually grow.
How so?
if I'm not always in front of the program does it restart slowly?

Thanks if you can help me
"edited"