PHP: this extension requires PHP 5.4+, version PHP 5.4.4 or never. The required PHP extensions are PCRE (enabled by default), and the memcached extension version 2.0.x.
The mysqlnd_memcache Memcache plugin supports all PHP applications and all available PHP MySQL extensions (mysqli, mysql, PDO_MYSQL). The PHP MySQL extension must be configured with mysqlnd support.
For accessing InnoDB tables, this PHP extension requires MySQL Server 5.6.6 or newer with the InnoDB Memcache Daemon Plugin enabled.
For accessing MySQL Cluster NDB tables, this PHP extension requires MySQL Cluster 7.2 or newer with the NDB Memcache API nodes enabled.