Read a great article about High Performace Web Site secrets on Skrentablog, called 14 rules for fast web pages. The list provided there is highly accurate and up-to-date.

List for Fast Web Pages

  1. Make fewer HTTP requests - Reducing 304 requests with Cache-Control Headers
  2. Use a CDN
  3. Use a customized php.ini - Creating and using a custom PHP.ini
  4. Add an Expires header - Caching with mod_expires on Apache
  5. Gzip components
  6. Put CSS at the top in head
  7. Move Javascript to the bottom
  8. Avoid CSS expressions, keep it simple
  9. Make CSS and unobtrusive Javascript as external files not inline
  10. Reduce DNS lookups - Use Static IP address, use a subdomain with static IP address for static content.
  11. Minimize Javascript - Refactor the code, compress with dojo
  12. Avoid external redirects - Use internal redirection with mod_rewrite, The correct way to redirect with 301
  13. Turn off ETags - Prevent Caching with htaccess
  14. Make AJAX cacheable and small

Sources & References

The full talk has details on what all of these mean in practice.

Recommendations

I recommend the article Speed Up Sites with htaccess caching to reduce the number of HTTP Requests. I also recommend hosting your static cacheable files on a separate subdomain, like z.askapache.com instead of www.askapache.com. You will also need to implement a version control system using mod_rewrite.

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