The Zend Optimizer is a free application can boost the performance of your PHP sites. It works by going over your code and optimizing it for faster execution. This means your site can load faster for your users while also utilizing less of the server resources.
Zend Optimizer can be enabled on servers with PHP 5.2 or higher (this includes most of our servers). To enable this feature, first add the two lines below to your .htaccess file in order to enable use of custom PHP settings. Be sure to replace [username] with your actual cPanel username.
AddHandler application/x-httpd-php52 .php
Next, you will need to enable the Zend Optimizer extension by adding the following line to your custom php.ini file (read http://www.inmotionhosting.com/support/website/general-server-setup/update-local-php-settings for more information on how to do this). This line can be added anywhere, though we recommend having it at the bottom of the file.
If configured correctly, a phpinfo page will then display “with Zend Optimizer v3.3.9″ as one of the available Zend modules. More information about creating a phpinfo page is available at http://www.inmotionhosting.com/support/website/general-server-setup/create-phpinfo-page-to-see-php-settings.