After upgrading my 1.17.1 server to 1.18 I started getting these errors.
Does not crash the game but is concerning.
[13:11:55] [IO-Worker-97/ERROR]: Failed to store chunk [1, -2]
java.util.ConcurrentModificationException: null
at java.util.HashMap$HashIterator.nextNode(HashMap.java:1597) ~[?:?]
at java.util.HashMap$KeyIterator.next(HashMap.java:1620) ~[?:?]
at oc.a(SourceFile:163) ~[server-1.18.jar:?]
at oc.a(SourceFile:476) ~[server-1.18.jar:?]
at oc.a(SourceFile:165) ~[server-1.18.jar:?]
at oi.a(SourceFile:128) ~[server-1.18.jar:?]
at oc.a(SourceFile:476) ~[server-1.18.jar:?]
at oc.a(SourceFile:165) ~[server-1.18.jar:?]
at oi.a(SourceFile:128) ~[server-1.18.jar:?]
at oc.a(SourceFile:476) ~[server-1.18.jar:?]
at oc.a(SourceFile:165) ~[server-1.18.jar:?]
at om.a(SourceFile:118) ~[server-1.18.jar:?]
at om.a(SourceFile:83) ~[server-1.18.jar:?]
at crb.a(SourceFile:79) ~[server-1.18.jar:?]
at cqy.a(SourceFile:174) ~[server-1.18.jar:?]
at cqy.a(SourceFile:164) ~[server-1.18.jar:?]
at aum$b.run(SourceFile:59) [server-1.18.jar:?]
at auk.g(SourceFile:91) [server-1.18.jar:?]
at auk.a(SourceFile:146) [server-1.18.jar:?]
at auk.run(SourceFile:102) [server-1.18.jar:?]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136) [?:?]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635) [?:?]
at java.lang.Thread.run(Thread.java:833) [?:?]
Comments 3
@unknown, please create a new issue in case you can reproduce this with the latest 1.18.2 vanilla server.
Not creating a new issue as we ran into this on a modded server, so not exactly reportable to Mojang, but leaving this here nonetheless for anyone who stumbles upon it (or whether a dev wants to look into it on their own accord).
1.18.2 with a few mods, but one (maybe important?) observation we made is that if the player who was causing the affected chunks to be loaded logged off, the issue would immediately resolve itself, server lag would stop and would not return upon the player rejoining. However, we can't verify whether the chunk actually saved or got regenerated as they were (old but) untouched chunks.
Started happening more consistently after building a few large farms, so it may be tied to tick lag or generally lower tick-rate.
it looks like this is not actually fixed, as it has happened on my 1.18.1 server twice in the past few months. it results in a chunk being deleted and forces it to regenerate from seed.
[media]i can provide more info, logs, etc. later tonight after work.