Java memory allocation
From MyWiki
The Java Virtual Machine takes two command line arguments which set the initial and maximum heap sizes: -Xms and -Xmx. You can add a system environment variable named _JAVA_OPTIONS (under Windows), and set the heap size values there. For example if you want a 512Mb initial and 1024Mb maximum heap size you could use: SET _JAVA_OPTIONS = -Xms512m -Xmx1024m
