Yes. Zend Optimizer™ for PHP5.2 is installed and enabled on all Linux hosting accounts. PHP 5.3 does not use Zend Optimizer. For more information, see Using Zend Guard Loader.
GD Library is a PHP library that affects image resizing, among other things. Zend Optimizer™ works with Zend Guard™ to enhance the performance of PHP applications. Zend Guard protects the source code of PHP applications by distributing them without revealing the application's source code. Zend Optimizer runs and optimizes Zend Guard's encoded files, which enhances the performance of PHP applications.
You can upload newer versions of Zend Optimizer (and other PHP modules) and reference the path to their files.
To use Zend Optimizer with our hosting accounts, you must disable APC. For more information, see Disabling APC on Your Hosting Account.
To enable Zend Optimizer on your hosting account, you must either modify or create a
php5.ini file. The file you create or modify must include the following code:
We recommend backing up your
php5.ini file before modifying it.