How to reproduce the performance issue

Generate a new world and notice how the chunkloading gets stuck a couple times. in my testing it got stuck on 17%, 42% and 82% for 5 seconds!!! this also happens when playing in the world. AE2 shouldn't slow down worldgen this much since it only generates meteorites.

Spark profile link

https://spark.lucko.me/6nk6mWuoUD

Which minecraft version are you using?

1.20

On which mod loaders does it happen?

Forge

Additional details

I recommend flying around in spectator mode to also see the pauses

No response

Your spark profile does not actually show AE2 using much CPU at all.

@shartte worldgen thread is probably not measured by spark though

Huh, true, it isn't :D
The only thing visible is the water reflowing on the main thread.

having pauses while loading sounds a strangely familiar to me to having long Garbage Collector cycles
try

-XX:+PrintGCDetails

in your command line options and check the log/minecraft console if those pauses correlate with printout about active GC processes ... 2.5GB sounds okayish to me but maybe your GC is working too hard ... the issue can be many things but adding a bit more ram ussually reduces the interval ... but can also increase the delay if there is some memory fragmenting programming involved :) but at least it would confirm my suspicion

better is optimizing the GC to your Game and PC setup

@Vikthos Rerun spark with /spark profiler start --thread *