Cf http://www.avricot.com/blog/?post/2010/05/03/Get-started-with-java-JVM-memory-%28heap%2C-stack%2C-xss-xms-xmx-xmn...%29 et http://www.mkyong.com/java/find-out-your-java-heap-memory-size/
-Xms<size> - Set initial Java heap size
-Xmx<size> - Set maximum Java heap size
-XX:PermSize<size> - Set initial PermGen Size.
-XX:MaxPermSize<size> - Set the maximum PermGen Size.
> -Xss = set java thread stack size