Same as Michael Iddisah...on 1.15.1 and 1.15.2, java server on macOS, whenever an apprentice cartographer is traded to the point that they try to level up to journeyman, the server crashes. I watched the java CPU usage, and when the level-up trade occurs, java CPU drops way off, the game stops, and nothing happens until max-tick-time is reached, when the server auto-kills itself. So whatever is going on isn't something that causes java to hammer the CPU.
Oddly enough, after putzing with this through multiple crashes, I tried setting max-tick-time to 120000. Same thing happened as before...but when we restarted the server, the cartographer had successfully become a journeyman. We had been testing with the same cartographer, and he was always still an apprentice after the crash, but not this time.
In the java server, my understanding is that the ocean monument map is generated by the apprentice and the woodland mansion map is generated by the journeyman. There's a significant difference in the spawn rate (odds?) of ocean monuments vs. woodland mansions. Maybe this has something to do with the problem?
Hashtag me too. Updated from 1.15.2 to 1.16.1.
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