Severe memory leak in minecraft, caused a crash and the entire PC to freeze, possibly caused by a datapack

This report has been set to private as the world contains a private version of the Terralith datapack that is avaiable to patreons only. Do not redistribute publicly or to anyone outside mojang

You might have some trouble reproducing this altough it did happen to me twice before

How to reproduce (hopefully)

• Create a world using this datapack [^v0.0.27a.zip]
• You should see the ram usage being quite normal at about 2GB
• Teleport by 10k blocks in one direction wait for the chunks to load in the area then teleport again
• This might be affected by biomes so when you're around 50k start looking for an eroded badlands
• Start flying around the eroded badlands for an hour doesn't matter what
• You you will begin to notice your game stuttering untill it becomes unplayable altough it will not crash
• If you relog the stuttering will get worse
• If you set the allocated ram to something higher like 12gb the game will be using around 7-9 GB's of ram for no reason and will never go back down

Or (updated for 1.18 pre1)

• Download the world save from the mega link (the world is almost 300MB in size)
• Replace the datapack v0.0.23a.zip with v0.0.27a.zip to laod the world
• You should notice the mentioned issue right away or the world won't even load
  https://mega.nz/file/RmJmSDKb#Oww8AYrHi02O9wI_txhLhrGGANbfb1zhpAaTHXc-g_E]

This has happened to me once more today. What I can take away from this is that, after exploring chunks for a while memory usage skyrockets and stays high even after relog, might be related to MC-239682 & MC-240589

I am pretty certain this is a memory leak. It maybe could be reproduced without the datapack but the game is unmodified vanilla