Every once in a while someone makes a site that becomes wildy popular. Having loads of people visiting all at once can put some serious strain on the server's resources and causes all sorts of problems as the congestion builds. Even if a site is not exceedingly popular, it is possible that it may come under a 'denial of service' attack from somewhere.

Before even thinking about setting up the throttling mechanism on a site, it is important to know what resources are at your disposal.

If you are unsure about what resources are available on your site, check with the hosting service and find out what they are providing. It's important to know the limitations of the hardware and network resources, but don't fall into the trap of believing this is the most important thing to know.

It's a tradition in the corporate world, especially banking, to throw extra resources at computing problems - buying the latest, fastest servers to help speed up slow applications, upgrading network hardware to allow data to travel more freely, and so on. Poorly designed software or software that is poorly tuned for performance always finds a way to utilize all the resources once can throw at it, and still want more.

More often than not , it is better to look at why software is chewing resources and see what can be done to either stop it or at least alleviate the problem, so that the software utilizes its resouces wisley. Drupal already has several strategies in place to help you, the site administrator, decide how and when to use resource intensive modules, and how to maximize the site's efficiency.

See next article's about caching and throttling