Regarding under-eye fillers, how long do the effects last?

The area under my eyes is sunken diagonally from the inner corners, making me look older and haggard. People often tell me I look tired, so it has been quite a bit of a stress for me. I want to fill in the sunken area to make the under-eye area look more even. I think fillers would be the most effective for adding volume, and since reviews seem to indicate high satisfaction, I am considering getting the procedure. However, the eye area moves frequently, and since the amount of filler used is small, I am worried it might be absorbed quickly. I am curious about how long the effects of under-eye fillers last. Also, if there are other procedures suitable for filling in the sunken area besides fillers, please recommend those as well.