I'm curious, because I don't know too much about databases. A basic drupal installation has 55 tablespaces. If you were to just use new prefixes anytime you configured a new site (and even if you didn't you'd only save so much room when it comes to number of tablespaces), how many could you have before it became too much for mysql to deal with?
I know at work the most I've seen is almost 600, but that's on Oracle databases where a single tablespace can be more than 2Gb and the system specs it's hosted on are absurd. What about a lowly linux box - pIII 500 with 192mb memory?
<EOL> Tib