Always Scalable. Always Fast. Always On.
XCache is a fast, stable PHP opcode cacher that has been tested and is now running on production servers under high load. It is tested (on linux) and supported on all of the latestPHP cvs branches such as PHP_4_3 PHP_4_4 PHP_5_1 PHP_5_2 HEAD(6.x).
Integrating APC (Alternative PHP Cache) Into PHP5 (Debian Etch & Apache2) This guide explains how to integrate APC (Alternative PHP Cache) into PHP5 on a Debian Etch system (with Apache2). APC is a free and open PHP opcode cacher for caching and optimizing PHP intermediate code. It’s similar to other PHP opcode cachers, such as eAccelerator and XCache.
This trick isn’t guaranteed to prevent all WordPress-generated PHP memory errors, but it certainly seems to help reduce their overall occurrence. For some reason, after my host upgraded their servers to Apache 1.3.41, I began logging an extremely high number of fatal PHP “memory exhausted” errors resulting from the WordPresscache.php script. Here is an example …
What is Memcached? Free & open source, high-performance, distributed memory object caching system, generic in nature, but intended for use in speeding up dynamic web applications by alleviating database load.
Controlling how web pages are cached is basically done using 2 kind of headers: Expires and Cache-Control