Whenever a person or an item goes through a nether portal there is a significant amount of block lag for the following few seconds, and in some instances crashing the server.
Not sure if it helps, but my server averages 5 people on it or more when the issue is noticable
Linked issues
duplicates 1
Comments 3
confirmed in 1.14.1 I am seeing huge spikes when entities enter a nether portal. I am not noticing it with end portals
Duplicate of MC-117914
Confirmed, My server is feeling the same thing. Anything goes in and it puts the server behind about a second. no rubber banding but people usually wind up with a few delayed block updates