I crock pot some stuff an usually takes between 10 to 12 hours. I have seen people smoke a pig which takes about 1 day. What were the rules of sacrifice in the ancient gods or the new one?

I mean it must have take a long while to light a goat or something similar on fire as a sacrifice. Do then the believers just go home come back the next day and keep lighting it till its down to ash? Or when it was burnt to a crisp did they use the meat to feed the villiage city or town?