magento installed on PHP

PHP is an interpreted scripting language. The process of running a PHP script includes a fewsteps - reading a script file from the hard drive, parsing and compiling bytecode, and finallyrunning that bytecode.Realpath cache configuration Optimization of file I/O is not only limited to using faster hard drives. It is also highlyrecommended to increase the default realpath_cache_size and realpath_cache_ttl values inphp.ini settings. Based on our tests the recommended values arerealpath_cache_size=32kandrealpath_cache_ttl=7200 on production servers.Bytecode cachingThe process of reading PHP scripts from disk and compiling them can be eliminated by enablingPHP accelerators. PHP accelerators cache compiled bytecode, resulting in less file and systemI/O. Well known PHP accelerators eAccelerator and APC are tested and fully compatible withMagento Enterprise Edition. Their built-in shared memory can also be used as Magento Themes Edition cache storage, which will be covered later in this document.php.ini configurationTo reduce the memory usage and speed up PHP performance you can enable in php.ini only theminimum set of PHP extensions required to run Magento Enterprise Edition. The necessaryextensions are:• PDO_MySQL• simplexml• mcrypt• hash• GD• DOM• iconv2• SOAP (if the MagentoWebservices API is to be used) !!"#$%&' ()' *#+',-%' -+../.0',.*'#$1%-'ABA',445/