I'm planning to host wikis for several different subjects. One will be a wiki for statistics programmers, another will be for natural childbirth, another will be for local politics. It is unlikely the groups will interact. They'll all run on the same box. My question: is it better to run multiple instances of mediawiki, where I extract the tarball to /var/www/wiki1, /var/www/wiki2, etc... or is there some internal support for this? Is running multiple wikis more CPU intensive than one single one? TIA