FPS rapidly decreasing in certain situations
I use a 16x PBR self-made texture pack that makes the game look nicer and helps it run alongside shaders like Complementary Reimagined which supports PBR. I am certainly aware that the pack is intensive but its worth mentioning that in previous versions of Iris and Sodium my game played at around 40FPS-lowest 80FPS-highest @ 20 RendDist - 12Sim.Dist -16ShadowDist - with tons of intensive mods.
Currently, im running my game at 16Rend.Dist - 8Sim.Dist - 10ShadowDist - Very Few Mods @ 1080p - RTX3070 - Ryzen 9 5900x - 8GB allocated. This gets me 160FPS-highest -10-Lowest
In other words my system is taking up significantly more resources since as far back as 1.19.3 and while I am aware this is partly because Minecraft is terribly optimised and makes frequent changes to its code. Slowdowns such as these have never been as bad before while mods such as Iris and Sodium have been installed at least. While it might at first look like a matter of hardware limitation, I have turned settings down super low to compensate for this performance issue but to no avail.
After installing Sodium 0.5.1 and Iris 1.6.7 I can confirm that the issue is still present. I've ruled out other potential sources of the problem by attempting to troubleshoot, but to no avail aswell. I hypothesised the following to be the source of the issue but troubleshooting them did not fix the issue:
-Turning shaderpack's shadow resolution and shadow distance down drastically and turning POM off.
-Changing shaderpack
-Changing Fabric &/or Quilt version
-Changed java (to adoptium) and its arrangements (From 8GB to more or less)
-Loaded up older (less intensive) versions of my resource pack
-Updated drivers
-Updated windows
-Systematically narrowed down mods that might cause the issue. (its definitely Iris or Sodium)
-Systematically bench marked performance with settings enabled vs disabled (There was no culprit)
Its worth mentioning that the areas my system tends to struggle in are mountainous biomes and foliage-intensive biomes. This is presumably due to the vast number of custom 3D models (flowers) and POM textures being loaded which of course takes up a lot of VRAM from my cards 8GB. While its true I only have 8GB of VRAM that was more than enough in previous versions of Iris/Sodium/Minecraft while right now, its bottle necking me.
But it also appears that slowdowns or drops in FPS don't occur with shaders turned off while in the same areas, even though the same resource pack is being used. So it would seem that Sodium's renderer is doing its job from what I can tell. The same issue also did not occur when using older versions of Minecraft and iris. That being said, there are compromises I have found that rectify the issue such as:
-Turning off shaders with resource pack enabled
-Turning down shader settings to potato quality
-Turning down render distance drastically (-8)
-Turning off resource packs with shaders enabled
Some clarification on whether or not this sounds like an issue with iris or if its just a matter of hardware would be very much appreciated. Thanks in advance for any help on the matter!
8 Replies
If you really want to figure out if there were performance regressions on iris' side I'd recommend grabbing the old release you used, generating a test world and copying it to a 1.20.1 instance with latest mod versions. Make sure you use the same configs, settings and shaderpack versions across these and use the same camera angle to make the comparison as fair as possible
Ok il give it a shot 👍
Right so it seems like 'something' is going on with the latest version of sodium/iris because frame rates while still a little instable have significantly improved. I cant narrow down which of the two mods are to blame however because later versions of sodium are incompatible with earlier versions of iris. Atleast we know its not entirely a matter of hardware limitation. I wish I had more technical knowledge to explain more on whats going wrong or atleast to investigate it.
the problem is because you are running out of VRAM
your GPU only has 8 GB of VRAM, but the screenshots where you show an issue have Sodium allocating 9 GB or more
something is going wrong because Sodium is only trying to use a small fraction of the memory it is allocating (<3 GB)
so there's like 6 GB just being wasted for unknown reasons
Yeah I suspected that tbh, I am not well versed in minecrafts f3 :waaaaaa:. But I reported the issue under VRAM Allocation in the iris's githubs issue section a couple of days ago. I wonder if its got something to do with virtual memory allocation. Mine is currently at 7167MB but is generally allocated by windows, though I dont see how that would affect VRAM allocation. Is it the case that the mod uses drivers to detect VRAM? Or does it just detect everything itself regardless of drivers/profiles. Its also worth mentioning that I am using the latest version of ATlauncher which might affect Nvidia's performance optimisations.
Ok so ive just loaded up the same instance on the vanilla launcher. The same issues is present, but whats interesting is that when shaders are not enabled, sodium refuses to render more than a single chunk at a time. When moving between chunks, they do not render in a gradient shape but rather one at time. This leads me into thinking that this is an issue with Nvidia drivers more so than the mod itself.
It looks like the https://discord.com/channels/774352792659820594/1141315985979220048 bug is somehow related but I cant be 100% sure.
Again thanks for the help and keep up the good work! 👍 👍
it's not the NVIDIA drivers and this bug has nothing to do with the GPU
it's just a bug in Sodium 0.5.1 with mods that disable fog
I know this is a dead thread but just wanted to say I fixed the inefficiencies in my game, it had nothing to do with sodium or iris, was entirely user end issue to do with the resource pack's models and im no longer experiencing any issues so feel free to close this thread and thanks for the help!