[MC-149356] Minecraft 1.14 server locks up when sysop kills mob

I installed version 1.14 a couple hours ago.

When I play using my op account and I kill a mob with any weapon the server locks up for a minute or more. Sometimes it recovers and continues, but about 70% of the time it disconnects the users with a "server timed out" message. So far I have one time that the server log shows the server software shut down the server.

[18:45:56] [Server thread/ERROR]: Something went wrong upgrading!

java.lang.OutOfMemoryError: GC overhead limit exceeded

at java.util.Arrays.copyOf(Arrays.java:3332) ~[?:1.8.0_112]

at java.lang.AbstractStringBuilder.ensureCapacityInternal(AbstractStringBuilder.java:124) ~[?:1.8.0_112]

at java.lang.AbstractStringBuilder.append(AbstractStringBuilder.java:448) ~[?:1.8.0_112]

at java.lang.StringBuilder.append(StringBuilder.java:136) ~[?:1.8.0_112]

at com.mojang.datafixers.types.templates.Named$NamedType.toString(Named.java:155) ~[minecraft_server.1.14.0.jar:?]

at java.lang.String.valueOf(String.java:2994) ~[?:1.8.0_112]

at java.lang.StringBuilder.append(StringBuilder.java:131) ~[?:1.8.0_112]

at com.mojang.datafixers.types.templates.Tag$TagType.toString(Tag.java:195) ~[minecraft_server.1.14.0.jar:?]

at java.lang.String.valueOf(String.java:2994) ~[?:1.8.0_112]

at java.lang.StringBuilder.append(StringBuilder.java:131) ~[?:1.8.0_112]

at com.mojang.datafixers.types.templates.Sum$SumType.toString(Sum.java:232) ~[minecraft_server.1.14.0.jar:?]

at java.lang.String.valueOf(String.java:2994) ~[?:1.8.0_112]

at java.lang.StringBuilder.append(StringBuilder.java:131) ~[?:1.8.0_112]

at com.mojang.datafixers.types.templates.Product$ProductType.toString(Product.java:232) ~[minecraft_server.1.14.0.jar:?]

at java.lang.String.valueOf(String.java:2994) ~[?:1.8.0_112]

at java.lang.StringBuilder.append(StringBuilder.java:131) ~[?:1.8.0_112]

at com.mojang.datafixers.types.templates.Product$ProductType.toString(Product.java:232) ~[minecraft_server.1.14.0.jar:?]

at java.lang.String.valueOf(String.java:2994) ~[?:1.8.0_112]

at java.lang.StringBuilder.append(StringBuilder.java:131) ~[?:1.8.0_112]

at com.mojang.datafixers.types.templates.Product$ProductType.toString(Product.java:232) ~[minecraft_server.1.14.0.jar:?]

at java.lang.String.valueOf(String.java:2994) ~[?:1.8.0_112]

at java.lang.StringBuilder.append(StringBuilder.java:131) ~[?:1.8.0_112]

at com.mojang.datafixers.types.templates.Product$ProductType.toString(Product.java:232) ~[minecraft_server.1.14.0.jar:?]

at java.lang.String.valueOf(String.java:2994) ~[?:1.8.0_112]

at java.lang.StringBuilder.append(StringBuilder.java:131) ~[?:1.8.0_112]

at com.mojang.datafixers.types.templates.List$ListType.toString(List.java:178) ~[minecraft_server.1.14.0.jar:?]

at java.lang.String.valueOf(String.java:2994) ~[?:1.8.0_112]

at java.lang.StringBuilder.append(StringBuilder.java:131) ~[?:1.8.0_112]

at com.mojang.datafixers.types.templates.Tag$TagType.toString(Tag.java:195) ~[minecraft_server.1.14.0.jar:?]

at java.lang.String.valueOf(String.java:2994) ~[?:1.8.0_112]

at java.lang.StringBuilder.append(StringBuilder.java:131) ~[?:1.8.0_112]

at com.mojang.datafixers.types.templates.Sum$SumType.toString(Sum.java:232) ~[minecraft_server.1.14.0.jar:?]

[18:46:15] [Server thread/ERROR]: Encountered an unexpected exception

m: Ticking entity

at net.minecraft.server.MinecraftServer.b(SourceFile:831) ~[minecraft_server.1.14.0.jar:?]

at ug.b(SourceFile:343) ~[minecraft_server.1.14.0.jar:?]

at net.minecraft.server.MinecraftServer.a(SourceFile:764) ~[minecraft_server.1.14.0.jar:?]

at net.minecraft.server.MinecraftServer.run(SourceFile:632) [minecraft_server.1.14.0.jar:?]

at java.lang.Thread.run(Thread.java:745) [?:1.8.0_112]

Caused by: java.lang.OutOfMemoryError: GC overhead limit exceeded

at ig.a(SourceFile:59) ~[minecraft_server.1.14.0.jar:?]

at ib.a(SourceFile:438) ~[minecraft_server.1.14.0.jar:?]

at ib.a(SourceFile:81) ~[minecraft_server.1.14.0.jar:?]

at ib.a(SourceFile:438) ~[minecraft_server.1.14.0.jar:?]

at ib.a(SourceFile:81) ~[minecraft_server.1.14.0.jar:?]

at im.a(SourceFile:113) ~[minecraft_server.1.14.0.jar:?]

at im.a(SourceFile:78) ~[minecraft_server.1.14.0.jar:?]

at im.a(SourceFile:74) ~[minecraft_server.1.14.0.jar:?]

at bxz.e(SourceFile:53) ~[minecraft_server.1.14.0.jar:?]

at us.f(SourceFile:693) ~[minecraft_server.1.14.0.jar:?]

at us.i(SourceFile:422) ~[minecraft_server.1.14.0.jar:?]

at us$$Lambda$2061/1024122718.get(Unknown Source) ~[?:?]

at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1590) ~[?:1.8.0_112]

at agh.h(SourceFile:135) ~[minecraft_server.1.14.0.jar:?]

at agh.p(SourceFile:114) ~[minecraft_server.1.14.0.jar:?]

at ve$a.p(SourceFile:438) ~[minecraft_server.1.14.0.jar:?]

at agh.c(SourceFile:123) ~[minecraft_server.1.14.0.jar:?]

at ve.b(SourceFile:114) ~[minecraft_server.1.14.0.jar:?]

at ve.a(SourceFile:100) ~[minecraft_server.1.14.0.jar:?]

at bhh.a(SourceFile:195) ~[minecraft_server.1.14.0.jar:?]

at bhk.a(SourceFile:100) ~[minecraft_server.1.14.0.jar:?]

at bhh.c(SourceFile:190) ~[minecraft_server.1.14.0.jar:?]

at bhh.e_(SourceFile:412) ~[minecraft_server.1.14.0.jar:?]

at bgr.a(SourceFile:52) ~[minecraft_server.1.14.0.jar:?]

at bgr$$Lambda$2650/1228356167.apply(Unknown Source) ~[?:?]

at bgr.a(SourceFile:153) ~[minecraft_server.1.14.0.jar:?]

at bgr.a(SourceFile:51) ~[minecraft_server.1.14.0.jar:?]

at aio.E(SourceFile:2435) ~[minecraft_server.1.14.0.jar:?]

at apt.a(SourceFile:32) ~[minecraft_server.1.14.0.jar:?]

at apz.a(SourceFile:95) ~[minecraft_server.1.14.0.jar:?]

at aow.a(SourceFile:107) ~[minecraft_server.1.14.0.jar:?]

at aov.a(SourceFile:32) ~[minecraft_server.1.14.0.jar:?]

[18:46:18] [Server thread/ERROR]: This crash report has been saved to: /Users/Marc/Desktop/Public Mincraft Server/./crash-reports/crash-2019-04-23_18.46.18-server.txt

[18:46:18] [Server thread/INFO]: Stopping server

[18:46:18] [Server thread/INFO]: Saving players

[18:46:24] [Server thread/ERROR]: Exception stopping the server

java.lang.OutOfMemoryError: GC overhead limit exceeded

logout

Saving session...

...copying shared history...

...saving history...truncating history files...

...completed.

But when I play on the same server, same version (1.14) using my non-op account (from the same client computer) everything works perfectly.

The server startup script says:

#!/bin/bash
cd "$(dirname "$0")"
exec java -Xmx2G -Xms2G -jar minecraft_server.1.14.0.jar nogui

.... which shows that the server is getting 2GB of memory to use.

========== update ========== 25 April 2019

Further testing reveals that if I use minecraft account #1 to deop account #2 ... and then re-op account #2 ... then the problem of account #2 causing a freeze has been eliminated.

Additionally, I have a third account that has op privileges on the server and after re-op'ing account #2 ... now account #3 (that was never deop'ed) no longer has the problem.

Summary: it appears that if just one op account gets deop'ed and the re-op'ed the problem for ALL op accounts is solved.