He has so much stamina that ill die someday

Ive been with my boyfriend for almost a year, and we are a fairly healthy couple. What I noticed since first having sex with him is that he is ~literally~ a beast with his incredibly high stamina, and sometimes, his sex drive too (but he self controls a lot). Sex normally lasts up to 3 hours, most of it being penetration because he takes awhile to cum. Unlike his high stamina, I dont have such high stamina, and my body is kind of weak.

Ive talked to him about his raging stamina, and as a result we try different things like longer foreplay, positions and the speed. Even then, the fastest record was 30 minutes and I dont complain with this time but that quick of timing is spontaneous and rare.

I am wondering if anyone else has a similar problem and if you could give me some advice as to how to drain his stamina more. I worry that I might not have good performance but he himself says its not because of me and we both worry he has some sort of dysfunction.