PHP opcache is a caching mechanism for PHP scripts that improves the performance of PHP applications by caching the compiled bytecode of PHP scripts in memory. This eliminates the need for the PHP interpreter to parse and compile the same script multiple times, which can significantly speed up the execution of PHP scripts.
How to enable PHP opcache?
To use PHP opcache, it must first be enabled in the PHP configuration. This can typically be done by editing the “php.ini” file and setting the “opcache.enable” option to “1”. That being said, if you are using any of our web hosting services on Koerge, OPCache is enabled by default, however can be disabled under cPanel > PHP Selector > Extensions.
How to configure PHP opcache?
Once enabled, the opcache can be configured using various options such as the amount of memory to be used for caching, the maximum number of files to be cached, and the maximum number of keys to be stored in the cache. If you are using Koerge web hosting, PHP opcache is configured for maximum performance for all customers.
How to check the status of PHP opcache?
To check if opcache is enabled and what settings are in place you can use the opcache_get_configuration() and opcache_get_status() functions. If you are using WordPress, you can simply install and activate the WP OPcache plugin.
Does PHP opcache work with dynamic features of PHP like eval() and create_function()?
No, opcache has some limitation, it will not work with certain dynamic features of PHP like eval() and create_function().
How do I reset the opcache if I’m frequently modifying my source code?
If you are using a opcode cache and you are modifying your source code frequently, it is recommended to reset the opcode cache manually or use opcache reset function, otherwise, your changes will not be reflected.
How much memory should I allocate for PHP opcache?
The amount of memory allocated for PHP opcache depends on your specific application and server. A general rule of thumb is to allocate around 64-128MB. If you are using Koerge, we assign 128MB of PHP OPCache for all customers.
In summary, PHP opcache is a powerful tool for improving the performance of PHP applications. It works by caching the compiled bytecode of PHP scripts in memory, which can greatly reduce the overhead of parsing and compiling the same script multiple times. With proper configuration and usage, PHP opcache can help to significantly speed up the execution of PHP scripts. However, it has some limitation and it’s important to be aware of those to make sure you are getting the most out of it.