Definitely a hyperbole. Hyperboles are extremely exaggerated statements. Saying someone snores louder than a freight train is impossible but it's VERY exaggerated. Therefore, it's a hyperbole.
It's not a simile since those use words like as and like, it's not personificatio because it's not giving non-liing things human qualities, I'm not sure what a hyperbole is but I'm almost 100% sure it's a metaphor...
