We run a Drupal site, and are expecting a sudden burst of users some time soon.
What are some of the best Drupal practices to handle sudden burst of: - User registrations - User Authentication
These operations are heavily dependent on database... so, how do we optimize that? Are there any techniques that minimize DB interaction during User Authentication? (for example: storing objects in memory, and writing them to DB at a later point in time?)
Any tips are greatly appreciated.
Some of the commercal drupal distros (like Aquia or presflow) have support for multiple DBs, this may help a little. I would say if your hardware is halfway decend you would have to have a major surge to worry.
User authentication and registration usually aren't processes that you can cache or delay (as in MySQL's INSERT DELAY). However, there are things you can do to alleviate some load. For example:
User registration and user auth is usually not a problem. Having a lot of users that are logged on can be a problem however. Drupal doesn't do much caching for logged in users. The reason is that the pages will look slightly different to each user when displaying user specific stuff. You can cache parts of a page which is the same for all to decrease the load. I don't have experience with it myself, but I've heard about a setup that did it. Doing this won't be that easy though.