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Linux
Ubuntu
Troubleshooting:
Minecraft running slow - my linux minecraft was running on 12 to 14 fps. i have installed hava 7,java 8, openjdk 7 and everything requires but minecraft stil slow
This command should tell you what is currently providing the Java virtual machine (java) and the Java compiler (javac):
file /etc/alternatives/java /etc/alternatives/javac
This assumes the "alternatives" system is working properly, which might not be the case, depending on how Java has been "messed up" in the past. To check this, run:
file `which java javac`
If the alternatives system is working correctly and being used by Java, then you should see:
/usr/bin/java: symbolic link to `/etc/alternatives/java' /usr/bin/javac: symbolic link to `/etc/alternatives/javac'