PHP APC (Alternative PHP Cache / Opcode Cache) is framework that optimizes PHP intermediate code and caches data and compiled code from the PHP bytecode compiler in shared memory. APC Opcode Cache is quickly becoming the de-facto standard PHP caching mechanism. (adsbygoogle = window.adsbygoogle || []).push({});PHP APC installation is very easy, example with Fedora / CentOS / Red Hat (RHEL) you can check following guides to see howto install it: