Alternative PHP Cache, is a free open-source opcode (operation code) caching plugin for PHP. If your host has installed APC cache this plugin allows you to flush the cache from within WordPress. Once activated, go to Tools -> Purge APC to send the command to flush the APC cache.
The plugin returns either ‘Success’ or gives a detailed error message if it is unable to run the command successfully.
Original Author: TJ Stein, inspired by Kaspars Dambis of konstruktors.com