PHP cache incredible increases the speed of a site. For instance, if request preparation takes 1.2 seconds, after cache enabling it will take 0.6 seconds (increase by about 50%). Particularly, it influences on WordPress significantly as well because it contains a lot of PHP code.
On some sites based on e.g. WAMP (Apache, MySQL and PHP bundle for Windows) PHP code cache is turned off by default so it’s better for us to check the settings.
The most popular way to do that is to use OpCache – a special PHP module that does code caching. In PHP 5.5 and above this module already integrated into.
How it works
OpCache provides faster PHP execution through compiled code caching and optimization. It improves PHP performance by storing precompiled script bytecode in the s
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