TIPThe Iris Project
•Created by on 5/5/2025 in #iris-issues
45-55% FPS Reduction using 1.21.5 compared to 1.21.4
I originally opened this as a bug report on Github, but I'd figure I would also put it here just incase: https://github.com/IrisShaders/Iris/issues/2732
The TDLR though is, fps seems to be around 45-65% of where it used to be in 1.21.4 (performance varries from different specs it seems). This only occurs when a shader is enabled at all, even disabling it (with the hotkey in my case) causes my fps to be normal like how they are in 1.21.4, 3 other people in this thread is having the same issue, and it seems that (if they are to be believed), there are another 8 people having the same issue too that are just casual players.
The difference this time (and I will update this in the bug report too later) is that the fabric1.8.12snapshot.jar does not solve this issue, I'm still getting the same FPS loss. This marks the affected versions now to 1.8.10-1.8.12snapshot for 1.21.5.
I'd like to know if anyone here is having similar issues (it doesn't look like to me this thread is a duplicate since the other threads regarding fps issues is not what I'm talking about in this case). I think it varries spec to spec too which is what makes this more difficult, and I'm using an Nvidia 1060 3GB GPU which complicates things since that snapshot.jar mentions AMD performance fixes.
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