Server: Windows 10 Pro x64
Hosted: locally, I manage on my servers.
PaperSpigot: 1.14.4 builds 207 and 209 (haven't tried earlier builds)
WorldBorder: 1.9.10
Dynmap: Dynmap-3.0-beta-6-spigot.jar
Plugins
latest.log file showing all exceptions and startup
Java: 1.8.0_202
PaperSpigot Server RAM: 4GB + MetaspaceSize=1024m MaxMetaspaceSize=2048m
Issue: from console, I initiated the wb fill pillagers 20 208 true and while the fill was going through the chunks in the center (spawn) over time it started having memory and thread dumps.

The wb fill behaves as if the chuck has been loaded and completes the process, but are not releasing (all or some) of the memory once done. Ultimately it runs out, we get a thread dump and it starts up again - but it keeps going thru the same cycle of holding memory without releasing. In the attached log about line 4001 you'll see the memory floating up/down until about row 7500 and from there it drops further until the dump is written when getting to 163MB free at line 7767. It gets worse from that point on until I stop the server, restart and then it repeats again.

Additional info: I did run dynmap fullrender first and it completed fine. Setup the border and shape in worldborder and tried to just use wb fill pillagers without the force=true and it would not fill the inside. Only with the force=true did it start writing to dynmap. If you need anything further, do let me know.

Not sure if this has to do with the new chuckloading that was introduced in 1.14.4 or problems with paperspigot - though the log says it is not. So, starting here and if we need to pull in the Paper guys, we can. Thanks!! --Steve

Sorry, the startup was cut off due to how many lines was written. Here is a the startup info.