A PHP accelerator is a PHP extension designed to improve the performance of software applications written in the PHP programming language.
The way these PHP accelerators work is by caching the compiled bytecode of the human-readable PHP. Normally, the PHP code is compiled and then executed at runtime but these tools cache the compiled code, saving the expense of compiling it and thus generally save a bit of CPU at the cost of some increased memory usage.
So what PHP acceleration can do is make the PHP execute more quickly, and execute in roughly half the time. To the user it is a combination of page generation time, network latency, and page rendering time.
In CloudJiffy the most popular accelerators used are:
- APC
- Xcache
- eAccelerator (works with PHP 5.3 and 5.4 only)
- ZendGuardLoader (works with PHP 5.3 only)
To activate the accelerator follow the instructions:
Click Config button for the server in the environment.
In the etc folder open php.ini file.
Uncomment one of the Accelerators:
extension=apc.so 
extension=eaccelerator.so 
extension=xcache.so 
extension=ZendGuardLoader.so
Also here you can make all settings necessary for your module.
Save the changes and restart the node.
That's all. Now the chosen PHP accelerator is activated.