how can I run multi wallet on one computer to share same blockdata you know ,you need a 32GB size for one bitcoin client,is it possible to run several bitcoin programs sharing same data source using -datadir or something else? I have found that somebody had put it  about a year ago and got an big NO; Since 1 year has passed ,is it still NO?
On Windows it wouldn't work because of file locking/sharing I suspect and on Linux that wouldn't be a problem but the data would surely get corrupted. There's no advantage to running multiple servers either, if you need to process more transactions than the server can handle then you should probably be doing it a different way or with multiple machines. If it's to help the network then one will do - leave it 24/7 and it will start to provide more than 8 connections if you allow it via config.