Cant turn without lag

Put the summary of the bug you're having here

What I expected to happen was that it was just my mouse that was lagging behind.
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*What actually happened was that I'm am lagging
when i join the nexusmc or any server i can't turn sometimes and when i try to turn i can't even move. I always lag and the computer i am on is always very efficient then all the sudden it doesn't just run smoothy

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
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