Description:

APC was conceived of to provide a way of boosting the performance
of PHP on heavily loaded sites by providing a way for scripts to
be cached in a compiled state, so that the overhead of parsing and
compiling can be almost completely eliminated. There are
commercial products which provide this functionality, but they are
neither open-source nor free. Our goal was to level the playing
field by providing an implementation that allows greater
flexibility and is universally accessible.

We also wanted the cache to provide visibility into it's own
workings and those of PHP, so time was invested in providing
internal diagnostic tools which allow for cache diagnostics and
maintenance.

Thus arrived APC. Since we were committed to developing a product
which can easily grow with new version of PHP, we implemented it
as a zend extension, allowing it to either be compiled into PHP or
added post facto as a drop in module. As with PHP, it is available
completely free for commercial and non-commercial use, under the
same terms as PHP itself.

APC has been tested under PHP 4.0.3, 4.0.3pl1 and 4.0.4. It
currently compiles under Linux and FreeBSD. Patches for ports to
other OSs/ PHP versions are welcome.

NOTE!: php4-apc has to be loaded last, very important!