Performance
- Use tracker and the administer>>log>>top visitors display. Check each URL of the biggest consumers and if they don't check out, use the "ban" link.
- Throttle module works but it annoys users and screws SEO unless you apply it carefully. Turn off modules that inmpact admin, not users
- MySQL Cache helps CPU and memory, but only if queries are going to be re-used i.e. enough activity http://www.databasejournal.com/features/mysql/article.php/3110171 - it will grab up to 20M memory!
- Prune unnecessary modules (and remnant tables from removed modules)
- php.ini file. set memory_limit = 20M if you can
- Look at throttle.module
- PHP caching such as APC is ‘essential” http://drupal.org/node/49365
- http://drupal.org/node/2601
- http://drupal.org/node/52656