I have got a problem. My program is really big and java is throwing OutOfMemoryException.
In `.bat` file, I have got the following: 

```
java -server -Dfile.encoding=UTF-8 -Xmx1500m -Xbootclasspath/p:../libs/l2ft.jar -cp config/xml;../libs/*; l2ft.gameserver.GameServer

```

Java is using 6 GB of my RAM, next 6 GB is not used.

I typed `System.getProperty("sun.arch.data.model");` and it says that I am using 64-bit JVM.