I would say there is 2 important factors:
- a good quality oven with a good airflow
- dry wood
My experience is that the smoke is visible the first 10 minutes or so then as the temp climb, it burns completely clean, no smoke, as the combustion is more complete.
If your wood is wet, I would say then the smoke may be a bit much the first 20 to 30 minutes but after that it will burn clean no matter what, ... , unless you put green wood with leafs