I made a similar report earlier, this one is a Crash that is happening on a Ryzen 3 CPU (Hopefully support model?) 32GB RAM
[02:45:31] [Server thread/ERROR]: Encountered an unexpected exception[02:45:31] [Server thread/ERROR]: Encountered an unexpected exceptionz: Exception generating new chunk at net.minecraft.server.MinecraftServer.b(SourceFile:880) ~[server.jar:?] at aam.b(SourceFile:312) ~[server.jar:?] at net.minecraft.server.MinecraftServer.a(SourceFile:816) ~[server.jar:?] at net.minecraft.server.MinecraftServer.x(SourceFile:674) ~[server.jar:?] at net.minecraft.server.MinecraftServer.a(SourceFile:261) ~[server.jar:?] at java.lang.Thread.run(Thread.java:831) [?:?]Caused by: java.util.ConcurrentModificationException at java.util.HashMap.computeIfAbsent(HashMap.java:1225) ~[?:?] at dbw.b(SourceFile:63) ~[server.jar:?] at dbw.a(SourceFile:53) ~[server.jar:?] at dax.<init>(SourceFile:43) ~[server.jar:?] at dam$a.<init>(SourceFile:200) ~[server.jar:?] at dam.a(SourceFile:187) ~[server.jar:?] at dam.a(SourceFile:128) ~[server.jar:?] at dal$a.a(SourceFile:40) ~[server.jar:?] at dal$a.a(SourceFile:31) ~[server.jar:?] at ctk.a(SourceFile:268) ~[server.jar:?] at cqw.a(SourceFile:36) ~[server.jar:?] at clv.a(SourceFile:309) ~[server.jar:?] at clv.a(SourceFile:292) ~[server.jar:?] at clx.e(SourceFile:53) ~[server.jar:?] at clx.a(SourceFile:231) ~[server.jar:?] at aay.a(SourceFile:563) ~[server.jar:?] at com.mojang.datafixers.util.Either$Left.map(Either.java:38) ~[server.jar:?] at aay.a(SourceFile:557) ~[server.jar:?] at java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:1146) ~[?:?] at java.util.concurrent.CompletableFuture$Completion.run(CompletableFuture.java:478) ~[?:?] at aba.b(SourceFile:58) ~[server.jar:?] at aqh.f(SourceFile:92) ~[server.jar:?] at aqh.a(SourceFile:132) ~[server.jar:?] at aqh.run(SourceFile:100) ~[server.jar:?] at java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1434) ~[?:?] at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:295) ~[?:?] at java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1016) ~[?:?] at java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1665) ~[?:?] at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1598) ~[?:?] at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183) ~[?:?][02:45:31] [Server thread/ERROR]: This crash report has been saved to: /home/acg/Server/./crash-reports/crash-2021-05-15_02.45.31-server.txt
Environment
Linux 5.4.0-70-generic #78-Ubuntu SMP Fri Mar 19 13:29:52 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
openjdk 16.0.1 2021-04-20
OpenJDK Runtime Environment (build 16.0.1+9-Ubuntu-120.04)
OpenJDK 64-Bit Server VM (build 16.0.1+9-Ubuntu-120.04, mixed mode, sharing)
Linked issues
duplicates 1
Attachments
Comments 3
Thank you for your report!
We're tracking this issue in MC-149777, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as Fixed. Please check the Fix Version/s field in that ticket to see in which version this behavior was or will be fixed.
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Regarding your comment, that's in fact a different issue: MC-227537
probably unrelated but this also appears in the logs periodically
java.lang.NullPointerException: Cannot invoke "it.unimi.dsi.fastutil.objects.ObjectSet.remove(Object)" because "☃" is nulljava.lang.NullPointerException: Cannot invoke "it.unimi.dsi.fastutil.objects.ObjectSet.remove(Object)" because "☃" is null at abe.b(SourceFile:202) ~[server.jar:?] at aay.a(SourceFile:914) ~[server.jar:?] at abj.a(SourceFile:460) ~[server.jar:?] at acd.a(SourceFile:944) ~[server.jar:?] at ua.a(SourceFile:114) ~[server.jar:?] at ua$a.a(SourceFile:42) ~[server.jar:?] at ph.a(SourceFile:21) ~[server.jar:?] at xh.run(SourceFile:18) ~[server.jar:?] at aqe.c(SourceFile:152) ~[server.jar:?] at aqi.c(SourceFile:23) ~[server.jar:?] at net.minecraft.server.MinecraftServer.b(SourceFile:766) ~[server.jar:?] at net.minecraft.server.MinecraftServer.c(SourceFile:161) ~[server.jar:?] at aqe.z(SourceFile:126) ~[server.jar:?] at net.minecraft.server.MinecraftServer.bd(SourceFile:748) ~[server.jar:?] at net.minecraft.server.MinecraftServer.z(SourceFile:742) ~[server.jar:?] at aqe.bn(SourceFile:111) ~[server.jar:?] at net.minecraft.server.MinecraftServer.y(SourceFile:726) ~[server.jar:?] at net.minecraft.server.MinecraftServer.x(SourceFile:678) ~[server.jar:?] at net.minecraft.server.MinecraftServer.a(SourceFile:261) ~[server.jar:?] at java.lang.Thread.run(Thread.java:831) [?:?][11:07:17] [Server thread/FATAL]: Error executing task on Serverjava.lang.NullPointerException: Cannot invoke "it.unimi.dsi.fastutil.objects.ObjectSet.remove(Object)" because "☃" is null at abe.b(SourceFile:202) ~[server.jar:?] at aay.a(SourceFile:914) ~[server.jar:?] at abj.a(SourceFile:460) ~[server.jar:?] at acd.a(SourceFile:944) ~[server.jar:?] at ua.a(SourceFile:114) ~[server.jar:?] at ua$a.a(SourceFile:42) ~[server.jar:?] at ph.a(SourceFile:21) ~[server.jar:?] at xh.run(SourceFile:18) ~[server.jar:?] at aqe.c(SourceFile:152) ~[server.jar:?] at aqi.c(SourceFile:23) ~[server.jar:?] at net.minecraft.server.MinecraftServer.b(SourceFile:766) ~[server.jar:?] at net.minecraft.server.MinecraftServer.c(SourceFile:161) ~[server.jar:?] at aqe.z(SourceFile:126) ~[server.jar:?] at net.minecraft.server.MinecraftServer.bd(SourceFile:748) ~[server.jar:?] at net.minecraft.server.MinecraftServer.z(SourceFile:742) ~[server.jar:?] at aqe.bn(SourceFile:111) ~[server.jar:?] at net.minecraft.server.MinecraftServer.y(SourceFile:726) ~[server.jar:?] at net.minecraft.server.MinecraftServer.x(SourceFile:678) ~[server.jar:?] at net.minecraft.server.MinecraftServer.a(SourceFile:261) ~[server.jar:?] at java.lang.Thread.run(Thread.java:831) [?:?]