Extreme world generation lag

It is to note that this is fixed by re-logging and it happens once per world as far as I am aware

I notice this too. I think it is because of the increase in height limit. I also thing they will have to improve the rendering engine to support the increased world limit.

Entire villager spawned in air of chunks.

Happened to me a few times, especially after teleporting. Reloading the world fixes it.

Could this possibly relate to MC-214902 ? The problem there also occurs when new chunks generate. The same issue here also happened while testing, and it seems somewhat related.

I am unable to reproduce in 21w08a

Even if i teleport as little as 200 blocks i can leave the computer on for 10 minutes and the chunks will not load untill i leave and rejoin the world

I can reproduce in 21w14a, though seemingly at random. When it happens, the chunks about (though not always centered) around where I teleported (all in about a 2-3 chunk circular radius) only generate if I relog or if they leave my render distance and then re-enter (but not if I force reload with F3+A). Interestingly, more chunks will appear to unrender based on location, relative to how close from that area I am. For example, no chunks will render if inside that circle, while a little further away only the ones opposite me from the circle will unrender, and, far enough away, only that circle remains unrendered (

)

Can confirm in 21w15a, but it doesn't occur as frequently.

Possibly not fixed in 21w18a? See screenshot and crash report.  Ignore screenshot, that seems to be a different issue. This issue seems to be similar but is still present in 21w18a: MC-224986.