I have done some work with Hibernate but am trying to get a sense of how well it would fit for a specific use case. I am looking to host 100-150 separate low volume projects (each with their own independent database) on a simple Linux dedicated server with 2Gb RAM. Right now they are running on a system with a home grown data abstraction system that I'm considering to port to Hibernate to get out of the ORM business.

My concern is the potential memory footprint of Hibernate. I totally get that the answer to "how much memory does Hibernate use" is that "it depends". What I'm trying to get a sense of is whether it seems plausible to have 100-150 sites each with their own hibernate project on a fairly small 2Gb RAM dedicated server.

Anyone running hundreds of separate hibernate projects on a relatively low powered server? Any thoughts on the plausibility of the use case for Hibernate?

Any thoughts/ideas/input appreciated . . .