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MC-158729

java.util.ConcurrentModificationException while updating neighbours

Resolved
Awaiting Response
3

The server crashed randomly after someone logged in, caused by a java.util.ConcurrentModificationException. No other players were online at that moment. The exception seems to be caused by the redstone wire in the attached screenshot.

1.14.4\: [^crash-2019-08-10_03.18.10-server.txt]

Description: Exception while updating neighbours

java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextNode(HashMap.java:1445)
	at java.util.HashMap$KeyIterator.next(HashMap.java:1469)
	at vk.a(SourceFile:1037)
	at bhr.a(SourceFile:233)
	at bov.a(SourceFile:154)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:317)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:322)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:317)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:322)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:317)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:322)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:317)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:322)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:317)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:322)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:317)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:322)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:317)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:322)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:321)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:322)
	at bqz.a(SourceFile:202)
	at bqz.a(SourceFile:340)
	at bvt.a(SourceFile:245)
	at bhr.a(SourceFile:353)
	at bhr.b(SourceFile:318)
	at bhr.a(SourceFile:309)
	at bhr.a(SourceFile:237)
	at boa.d(SourceFile:71)
	at bue.T_(SourceFile:19)
	at bhr.K(SourceFile:624)
	at vk.a(SourceFile:405)
	at net.minecraft.server.MinecraftServer.b(SourceFile:835)
	at uk.b(SourceFile:343)
	at net.minecraft.server.MinecraftServer.a(SourceFile:774)
	at net.minecraft.server.MinecraftServer.run(SourceFile:642)
	at java.lang.Thread.run(Thread.java:748)

Attachments

2019-08-10_10.01.36.png 2019-08-14_16.53.15.png 2019-09-01_01.56.10.png
crash-2019-08-10_03.18.10-server.txt
crash-2019-08-14_14.46.19-server.txt
crash-2019-08-31_23.47.34-server.txt
crash-2019-09-16_05.15.48-server.txt
crash-2019-12-09_14.48.05-server.txt
crash-2019-12-27_15.08.17-server.txt

Comments 9

It happened yet again, this time caused by a different redstone wire. This time there were two other people online, who got disconnected with a "server closed" message.

Another crash yet again, at the same gate as the second time. I will download and attach the world so someone can maybe look to see if something is wrong.

Edit: this time the server didn't crash when someone logged it, but when someone returned from the end.

The save file is quite large, even when zipped (1.7GB) so I uploaded it to a different site instead. https://gofile.io/?c=TRXYYg

The locations the crashes happened at are in the screenshots.

Another crash, at the same location as the last one.

We just had this same exception occur.   The coordinates are located at a redstone timer that was opening a trapdoor to let a water stream drop down.  crash-2019-12-09_14.48.05-server.txt contains the full crash report.

This happened again on our server. The world file is 9.32 GB, so I think it may be an error that occurs in large worlds?

[media]

As far as we are able to figure out on our server, this seems to also be the mob farm that is causing MC-158466 as both only occur while the same chunk or chunks are loaded, but we are unable to fully confirm.

Please check if that's still an issue for you in the latest 1.15.2 stable release or the latest 1.16 development snapshot.

I experienced this in 20w45a, but I don't know if it is the same error

Is this still an issue in 1.16.4 or later?

Jeuv

(Unassigned)

Unconfirmed

Crash

1.14.4

Retrieved