Iris 1.7.1 for Versions 1.21 and 1.20.5&6 very poor performance
I've been using Iris shaders since 1.20.1 and until/including 1.20.4 I've had great performance (150-160FPS). Since 1.20.5 the performance has been very poor (9-12FPS) and I don't know why. I assumed it had something to do with the devs wanting to wait until 1.21 and then fix the performance or smth (that's why I waited on saying anything), but nothing has changed.
The only mods I'm running in both versions are:
- Iris
- Fabric
- Sodium
Additional Info:
The shader seen in both screenshots is Complementary Reimagined (unchanged, set to: medium; integrated PBR+).
I am not running any resource packs, plain vanilla.
Both screenshots are made on the same seed, newly generated for each version. I've made sure that I've been in each world for long enough so that minecraft isn't generating new chunks anymore.
The game is set to 16 chunks render & simulation distance.
Minecraft was running with 90 FOV.
My resolution is 1440p.
PC stats:
- 12th Gen Intel Core i5-12600K 3.69 GHz
- Windows 10 Pro
- 16gb Ram (of which I've given minecraft 8gb for both versions)
- AMD Radeon RX 6800 XT
(I've had to force windows to treat the javaw file as high priority a while back so minecraft actually uses the graphics card)
Has Iris (or minecraft itself) changed significantly code-wise between versions?
Does anyone know of any fixes to this problem?
Devs, does this help or do you need more information?
Solution:Jump to solution
I've figured it out!
In the video it was enough to set the javaw file to high performance. Since 1.20.5 one has to set the other java file named java in that folder to high performance too....
14 Replies
Make sure debug mode is off, this caused serious issues for people the last time Iris was updated.
I can't remember how to do that myself but I know it causes massive performance drops if it's on and you don't know about it.
Thanks for the suggestion. I just started mc again to try that, but it didn't make a difference at all for me.
That's odd
do you have VSync on?
let me check
It's off
Ok then I have no idea what could possible be happening
Drivers maybe?
They should be on the newest version, I've updated them 1 or 2 weeks ago.
Yeah that's very odd indeed. I don't remember anyone else reporting issues like this with such a massive FPS drop
Minecraft is using your integrated graphics
make sure your monitor is plugged into your graphics card, not the motherboard, then follow this tutorial to make Minecraft use your 6800 XT: https://www.youtube.com/watch?v=J1UcsKnIV10
GameTrick
YouTube
How to Use Dedicated GPU on Minecraft - Minecraft Not Using Dedicat...
In This Video We Will See How to Use Dedicated GPU on Minecraft or Minecraft Not Using Dedicated GPU AMD & Nvidia
Here Are The Steps to Use Dedicated GPU on Minecraft or Minecraft Not Using Dedicated GPU AMD & Nvidia
1. Minimize Minecraft
2. Right-Click on Taskbar
3. Click Task Manager
4. Click More details
5. Click Details
6. Right-Click on j...
btw this is how you can tell what graphics are being used. This is on the right side of the F3 menu
This is what it should be, and what it is on your older instance
...I see this was already answered elsewhere. Why do people love asking the same question in multiple channels?
That's on me, I haven't ever used this Tags feature in dc before so I originally typed my question out here but couldn't send it because I didn't notice I had to actually attach a Tag to the post 😅. I was frustrated and just copied it and put it in #iris-help and then realised why I couldn't post this post here.
Solution
I've figured it out!
In the video it was enough to set the javaw file to high performance. Since 1.20.5 one has to set the other java file named java in that folder to high performance too.