What is the approximate Roster size per user?

Hi,

We have 210 users (actually those are java back-end apps) logged into the openfire server at all times. We setup the roster size (cache.username2roster.size) to 32MB. And we are seeing warning in the log something like “Roster cache filled up, compacting to 90%” something like it. What is the Roster size for one user approximately? And we are not sure how the parameters cache.username2roster.size and cache.username2roster.maxLifetime affect the openfire performance.

To me 32MB for 200 users seems a lot, is it not? How about systems that handle thousands of users? Are there any other parameters that we need to take care or we missing?

Please shd some light here.

Thanks

Yuva