How to flush the APC cache in Prestashop

In the backoffice of Prestashop, there is no option to flush the cache (Advanced parameters - Performance), it is only possible to disable the cache.

Different types of cache and how to flush them

Smarty compile cache: Delete the subfolders under cache/smarty/compile
Smarty template cache: Delete the subfolders under cache/smarty/cache
Cache using Filesystem: Delete the subfolders under cache/cachefs

But how can I go about flushing the cache if I use APC Cache ?

A subsidiary question: Is it possible to set a global ttl ? By default, everything gets cached forever.

Solution

To flush the APC user cache, you have to install the administration interface for APC (apc.php). This file is bundled with the download for APC. Just copy it to a folder that is accessible from the web, the edit it to set a password.
After that, you can connect and flush the cache when needed. It is possible to flush the system cache and the user cache separately.