Storing Symfony2 sessions in memcached

config.yml

imports:                                                                                                                                                                                                           
    # ....
    - { resource: services/session.yml }


framework:
    # ....
    session:
      handler_id:     session.handler.memcached

parameters.yml

parameters:
    # ...

    session_memcached_host:     localhost
    session_memcached_port:     11211
    session_memcached_prefix:   sess
    session_memcached_expire:   3600

session_services.yml

services:
    session.memcached:
        class: Memcached
        calls:
            - [ addServer, [ %session_memcached_host%, %session_memcached_port% ]]

    session.handler.memcached:
        class:     Symfony\Component\HttpFoundation\Session\Storage\Handler\MemcachedSessionHandler
        arguments: [@session.memcached, { prefix: %session_memcached_prefix%, expiretime: %session_memcached_expire% }]