Description of the issue

Noticed some new multiblocks in IP recently and set them up to give them a try. As it was a test world, I set up some creative bins to feed bitumen into the Coker and had the output collected by IE belts and sent to a black hole unit/tank. After leaving it running overnight I came back to see my game had largely become unresponsive. No crash, just severe TPS lag.

Versions and Modlist

ImmersiveEngineering-1.16.5-5.0.0-135
ImmersivePetroleum-1.16.5-3.3.0-4
Forge 36.1.16
Possibly unrelated Crash log for the rest:
crash-2021-03-31_23.03.54-server.txt
This was generated when I force quit the game due to it being unresponsive.

Crash Log

Not a crash log, since it didn't actually crash directly. But I was able to profile it with VisualVM. Saved a snapshot and am including it here.
snapshot-1622465184292.zip

Closing due to not being reproducable in any way

I cant for the live of me reproduce this, while also having VisualVM running in the background

I have a suspicion it was right on the edge of loaded chunks. If I recall correctly, however, when I went over to clean it up there were just piles of output items sitting on the belts, not moving

hm, could've perhaps been the items then~

most likely, just seemed odd for them to accumulate like that