This might be a silly thing to ask, but why don't they save their data in flat files on a shared filesystem?
They wouldn't need Memcached, since the OS caches files anyway; replication with rsync becomes easy; they don't need transactions anyway; and they wouldn't have so much software to manage.
They wouldn't need Memcached, since the OS caches files anyway; replication with rsync becomes easy; they don't need transactions anyway; and they wouldn't have so much software to manage.