You should read the documents, especially the part about the eviction policies.
Performance numbers are coming, but now right now.
P.S.: the updated documents for JBossCache 1.1 are currently only available via CVS head, but will be part of the JBossCache download, and will also be posted on jboss.org. JBossCache should be released next week.
Could you anyone get the Cvs path to download the jBossCache stuff.
1. download jboss-head from the CVS (there are docs on how to do this)
2. go to jboss-head/cache/docs/html
The docs are there in HTML