How much RAM would I need for a minecraft server that would be using A LOT of Movecraft?

I'm thinking of starting a pirates server that would make it possible to sail your own ship as well as hunt automated merchant ships… I know that a lot of movecraft servers have a lot of lag but this one would probably have more seeing as it would have the automated ships as well as the player ships. Would it be possible to run a server like this (with minimal lag) on about 3GB of RAM?

The recommended RAM is 1GB and you have 3GB so you should be okay. Also lag could be a server issue or an issue with people's Wi-Fi/modems/routers.