* - lockServers : Associative array of server names to "<IP>:<port>" strings.
* - srvsByBucket : Array of 1-16 consecutive integer keys, starting from 0,
* each having an odd-numbered list of server names (peers) as values.
* - memcConfig : Configuration array for ObjectCache::newFromParams. [optional]
* If set, this must use one of the memcached classes.
* - lockServers : Associative array of server names to "<IP>:<port>" strings.
* - srvsByBucket : Array of 1-16 consecutive integer keys, starting from 0,
* each having an odd-numbered list of server names (peers) as values.
* - memcConfig : Configuration array for ObjectCache::newFromParams. [optional]
* If set, this must use one of the memcached classes.