The main benefit of APC is to increase the performance of PHP scripts.
How to install APC on WAMP 2.1:
1) Go to http://downloads.php.net/pierre/
2) Download php_apc-3.1-svn20101116-5.3-vc6-x86.zip
3) Copy php_apc.dll to \wamp\bin\php\php5.3.5\ext
4) Enable php_apc extension from WAMP server panel -> PHP extensions
5) Open php.ini \wamp\bin\apache\Apache2.2.17\bin and add this:
[APC] apc.enabled = 1 apc.shm_segments = 1 apc.shm_size = 64M apc.max_file_size = 10M apc.stat = 1
6) Restart Wamp server
7) Open this address http://localhost/?phpinfo=1 in your favourite browser
And check for this section:
If you see that section, then everything is ok and you successfully installed APC extension on your WAMP server.
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