How to tell what GPU an app is running on?
I'm running an eGPU setup on macOS 10.13.4, and I am curious if there is any way to monitor whether an app is running on the external GPU or internal. Is there any developer tool or anything that will explicitly state which GPU an app is running on? I know Activity Monitor shows if an app is activating the dGPU in my MacBook Pro, but it doesn't seem to offer any way to distinguish between the dGPU and an eGPU, unless I'm missing something.
Launch Activity Monitor, then press CMD + 4 to see GPU History. Do things in the app and see which GPUs respond. Set update rate to Very Often for best results.