Problem Often Java Crashes (Ultimate)

[Mikeambrose3]

Hello,

Every 3 hours or so my server is getting random java crashes and it's outputting hs_err_pid logs every time. Since it's a java crash the server doesn't save and there is always a large rollback. Anyone know what is wrong?

Here is the hs_err_pid log file. There's also a 4.5GB~ .md.mp for each error file, however I'm now sure what these are for.

Pastebin:
http://pastebin.com/Y0PJSTWc

This is running on a Windows 2012 server with the latest Java 7 JDK/JRE. As before, since this is a java related crash there's no crash reports from Minecraft itself, so I'm left clueless at the cause. With many players online it's impossible to pinpoint the cause.

 

[cjm721]

Looks like you might be running out of perm gen space.
Also from looking at your JVM arguments:

Xmx26G -Xms3G -Xmn512M -XX:+UseG1GC -XX:+AggressiveOpts -XX:+UseFastAccessorMethods -XX:TargetSurvivorRatio=90 -XX:MaxGCPauseMillis=200 -XX:MaxPermSize=256m
java_command: mcpc.jar

I have not used <-XX:+UseFastAccessorMethods -XX:TargetSurvivorRatio=90 -XX:MaxGCPauseMillis=200> and when it is a JVM crash that appears to be due to memory management I would guess it has something to do with the garbage collector not working as intended. Personaly here is the start script I use for my 30-50man server:

/usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java -server -Xmx16G -XX:UseSSE=4 -XX:+UseConcMarkSweepGC -XX:+UseCMSCompactAtFullCollection -XX:+UseParNewGC -XX:+DisableExplicitGC -XX:+AggressiveOpts -XX:-OmitStackTraceInFastThrow -jar ultimate.jar nogui

I also see your alocating 26G of memory to the server but are you using that much? If your never/very rarely using more then ~60% I would suggest decreasing the dedicated memory and that will force the GC to be more efficient. So first I try with taking out some of the arguments and then if that does not work increaseing the perm gen your giving even more, but how many people do you have on the server as I rarely see mine go above 50% with 256M dedicated.

1. compacting perm gen total 79872K, used 79156K [0x00000007f0000000, 0x00000007f4e00000, 0x0000000800000000)
2. the space 79872K, 99% used [0x00000007f0000000, 0x00000007f4d4d2c8, 0x00000007f4d4d400, 0x00000007f4e0000

 

[Mikeambrose3]

-snip-

I actually didn't even think about the memory.. I'm running a Craftbukkit server alongside using the same command (both with 26G allocated, lol..). Guess that's one of my issues. Thanks for the detailed post, really appreciate it.