How to give more ram to the server?

[Foge]

Hello, I am trying to add more ram to the server and have 8gb available, but whenever I try to change this:

java -Xms512M -Xmx1G -jar ftbserver.jar

It simply always still runs at 512mb, regardless of what I change it to.

Thanks for anyone that can help

 

[SphinX]

-Xms512M is the minimum ram, -Xmx1G is the maximum, try setting -Xms2G -Xmx4G.

You may not notice any extra ram usage, but once you get more and more machines + constantly loaded chunks, it will start to use it.