Not to drop any spoilers (hide this comment before reading further ....)

But "The Amazing Digital Circus" explores this concept relating to human brain scans, and how the 'simulated' brains would react under simulation.

Similarly, the story Lena by qntm.[1]

It describes in part how some volunteer brain scans are actually quite agreeable to work with until they work for too many hours, and then they get fussy, but it's cool, you can always reboot them. But you need to hide from them the fact that it's been decades since they were scanned and uploaded, or they'll realize how long they've been slaves for.

1. https://qntm.org/mmacevedo