Question

I’m building a PHP site, but for now the only PHP I’m using is a half-dozen or so includes on certain pages. (I will probably use some database queries eventually.)

Are simple include() statements a concern for speed or scaling, as opposed to static HTML? What kinds of things tend to cause a site to bog down?

Answer 1

Strictly speaking, straight HTML will always serve faster than a server-side approach since the server doesn’t have to do any interpretation of the code.

To answer the bigger question, there are a number of things that will cause your site to bog down; there’s just no specific threshold for when your code is causing the problem vs. PHP. (keep in mind that many of Yahoo’s sites are PHP-driven, so don’t think that PHP can’t scale).

One thing I’ve noticed is that the PHP-driven sites that are the slowest are the ones that include more than is necessary to display a specific page. OSCommerce (oscommerce.com) is one of the most popular PHP-driven shopping carts. It has a bad habit, however, of including all of their core functionality (just in case it’s needed) on every single page. So even if you don’t need to display an ‘info box’, the function is loaded. On the other hand, there are many PHP frameworks out there (such as CakePHP, Symfony, and CodeIgniter) that take a ‘load it as you need it’ approach.

I would advise the following:

1. Don’t include more functionality than you need for a specific page
2. Keep base functions separate (use an MVC approach when possible)
3. Use require_once instead of include if you think you’ll have nested includes (e.g. page A includes file B which includes file C). This will avoid including the same file more than once. It will also stop the process if a file can’t be found; thus helping your troubleshooting process 😉
4. Cache static pages as HTML if possible – to avoid having to reparse when things don’t change