Sorry for not having such papers.
For JForum 2.1.8, I would say you'll have to
test. The cache engine is pluggable, which means you can use
JBoss TreeCache / eHCache with JGroups support and cluster the content, but that's not officially supported.
I personally run a 2 million pageview / month forum with 50k+ users and 600k+ messages without any problem.
Rafael
[originally posted on jforum.net by Rafael Steil]