Can't keep up! Is the server overloaded?

Hello good afternoon, I am constantly having this error in my spigot.

How can I solve that?



Are players discovering non-generated chunks? It could cause lag if you haven’t pre-generated your world. That way when players travel the server won’t be generating all the new chunks.

Yes, players are discovering the chunks, how can I Pre-Generate them?

Using a Plugin called WorldBorder, you can set a border of your world and then use /wb world fill and then confirm it. It will be slow but once you pre-generated a world there won’t be any lag due discovering new chunks. Also while running /fill it will be barely play-able so set aside some time for it.

I also receive this error but in my case the server is idle, no players at all. Started with the 1.17. update, prior to that all was well. My server is well beyond the system requirements posted for PaperMC:
i5-4570 3.2GHz 16GB RAM Win10 OS. Server Command Line:
java -ms4076 -mx9216 -jar paperclip.jar --nogui -o true