Php – Can the APC cache be shared among multiple PHP processes running as fastcgi/fcgid

Problem solved. The trick was to use the following lines

FastCGIExternalServer /var/www/fast-cgi-fake-handler -host 127.0.0.1:9000
AddType application/x-httpd-fastphp5 .php
Action application/x-httpd-fastphp5 /fast-cgi-fake-handler

The relative path in Action + the full path in FastCGIExternalServer did it!

APC does not currently share its cache between multiple php-cgi workers running under fastcgi or fcgid. See this feature request for details: "this behaviour is the intended one as of now".

One workaround is to allow PHP to manage its own workers. You can do this using the PHP_FCGI_CHILDREN environment variable in your wrapper script (plenty of examples all over the web for that). You should also stop fastcgi/fcgid from spawning more than one PHP process if you want to use this method.

The disadvantage with PHP_FCGI_CHILDREN is that its management of the workers is not as good as that provided by fcgid/fastcgi.

So, there we are. APC in a fcgid/fastcgi environment means giving each PHP worker their own cache, or disabling fcgid/fastcgi's process spawning in favor of PHP's built-in management. Let's hope this changes in the future.