The last step is the server configuration. Since you have follow the previous steps - you site should be pretty fast now and the server configuration will allow to improve it a little.
The first step is caching, it will allow to left the loaded things on the customer computer. It's good since the css/js (and may be some other general for all of the pages things) won't be loaded each time the new page is loading. It's possible to make by the following in the .htaccess (or in the apache config): «ifModule mod_expires.c>
ExpiresActive On ExpiresDefault "access plus 1 seconds" ExpiresByType text/html "access plus 1 seconds" ExpiresByType image/gif "access plus 2592000 seconds" ExpiresByType image/jpeg "access plus 2592000 seconds" ExpiresByType image/png "access plus 2592000 seconds" ExpiresByType text/css "access plus 604800 seconds" ExpiresByType text/javascript "access plus 216000 seconds" ExpiresByType application/x-javascript "access plus 216000 seconds"
</ifModule> </code>
Also you can use the apache mod deflate to improve the loading if the pages are big:
<FilesMatch .*\.js$> RewriteEngine On RewriteCond %{HTTP_USER_AGENT} !.*Safari.* RewriteCond %{HTTP:Accept-Encoding} gzip RewriteCond %{REQUEST_FILENAME}.gz -f RewriteRule (.*)\.js$ $1\.js.gz [L] ForceType text/javascript AddOutputFilterByType DEFLATE text/javascript </FilesMatch> AddOutputFilterByType DEFLATE text/css AddOutputFilterByType DEFLATE text/plain text/html text/xml
For the php speed up, some module, which will compile and store the compiled php files are required. It can be Zend, but for me the eAccelerator is preferable, The installation instructions can be found here./wiki/InstallFromSource