If you load up any vanilla world and start looking around, you'll find that chunk loading messes with your mouse sensitivity and response time. This makes the game unplayable, even on a decent gaming laptop. If you fly around in creative, it gets even worse than it already is in survival when walking or running around. This is a critical performance bug that affects 1.21.
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[MOD] Greymagic27
Dee23Gaming
A video won't show anything useful. It's a mouse sensitivity lag problem, not a graphical problem. But if you STILL want a video, then just tell me.
[MOD] Greymagic27
Will it not show how the mouse sensitivty changes when loading in chunks? Otherwise it's going to be hard to find a good repro case for this bug
Dee23Gaming
Well, I showed how to reproduce the bug. It's a feeling when turning the camera that something isn't right. When a game has lag spikes, or frame drops, the mouse sensitivity should never be affected, no matter what. But in this update of Minecraft Java, the sensitivity is not consistent, and the sensitivity seems to sync with frame drops when loading chunks in vanilla Java Minecraft.
[MOD] Greymagic27
Could this be MC-273262?
Dee23Gaming
No, it's definitely not MC 273262. That's just ordinary performance issues. This bug report of mine has to do with frame drops affecting the consistency of the mouse sensitivity.
[MOD] Greymagic27
I more meant the core of the issue which is frame drops when crossing chunk borders, but I will see if I can reproduce this behaviour tomorrow and get back to you.
Dee23Gaming
Thanks, let me know. I'm aware that Java Minecraft performs badly on vanilla, so anything to do with frame drops is quite "normal" to me at this point. These can be fixed with performance mods, which is a must-have for anyone playing Java. But in 1.21, these "normal" frame drops are now affecting the consistency of the mouse sensitivity, which in my over 11 years of consistently playing Minecraft, has never happened before.
kelianor
Does MC-239565 explain your issue?
Dee23Gaming
Yes, but the weird thing is that I didn't experience this bug in the versions they mentioned in that bug report. So according to me, this bug didn't exist prior to 1.21, but according to them, they experienced the bug way before 1.21. Really strange.
[MOD] Greymagic27
Thanks for finding MC-239565. Going to resolve this report into that one
migrated
I think I have the same problem as Warren. I will try to show you the problem in "MOUSE LAG".
The problem occurs when the world starts, I was moving with all my strength the mouse and as you can see the lag makes the movement go like choppy.
It also happens when you go at high speed and there is no time to generate the chunks.
We do not have enough information to find the cause of this issue.
Please record a video of this happening and attach it to this report.
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This issue is being temporarily resolved as Awaiting Response. Once the requested information has been delivered, the report will be reopened automatically.
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