The database settings are very well tuned and would say they are not a direct cause of locking up. Some vBulletin settings may make the difference, such as similar threads search, viewing users in forums and discussions, immediate view / visit update, some of the scheduled tasks, and of course some vBulletin products/plugins.
The largest board I've been looking after was 12 million posts, and reducing the extra features down to the bone helped to increase the speed noticeably, which also has a positive side effect on database operations. However that server had only a single master database, so I can't tell...
|