In android studio 3.0 there are two options(Run and Profile) available to run the application.
Both are functioning like the same thing and behaviour. See below screenshot:
and 
My question is what's the actual activities between the Run and Profile in android studio 3.0
As per Android studio team:
It's mostly a nice UI shortcut to open the profiler tool window and start profiling in conjunction with running the app. Clicking "Run" doesn't start the profiler, but you can still choose to profile the app later by opening the tool window.