Hey yall, I'm new here. I just thought I'd come in to report that I'm experiencing the exact same issue. On 1.21.4, I would be able to obtain 140 FPS on high settings with BSL shaders but in 1.21.5, I'd be lucky if I got 100 (averages 88-104 fps max) in the exact same location (same seed) but I'm using an Intel Core i7 13700K and an RTX 4070 with 32GB RAM, so I don't think the issue is entirely on solely using AMD CPUs and or GPUs. I'm using the latest drivers, newest version of Windows 11, everything's up to date.
The issue only happens with shaders enabled.
I tried Complementary with Euphoria Patches and that performs equally as bad -- in 1.21.4 in the same location of the same seed, I would get anywhere from 140-150fps and in 1.21.5 I'd be averaging in the 103-111 fps range. That's an almost 40-50 fps drop. I've tried everything in the book to fix it on my end, even adjusting the shaders so that they're on the lowest setting still grants me the same amount of FPS as it would on high settings which is the really weird part to me. Is this an issue on Mojang's end, Sodium's, Iris' (I don't think it's individual shaders; seems to affect all of them equally performance-wise) and if so, do they know of it and will they fix it?
Sorry for the long message. Thanks for yall's help in advance!
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