I'm looking to replace memcached. We have a LOT of traffic to our central memcached node which I'd like to split. There's only so much trunking networks I can do.

My general idea is to install a memcached-type daemon on every webserver and have the daemons replicate set/delete/updates over all the daemons, so that each webserver connects to a socket or on localhost. All data should be available on all nodes.

The alternatives: - repcached (max 2 masters) - redis (single master) - couchdb/mongodb/handlersocket - persistent data on disk, I'd like to remove the disk part to gain more performance.

Any hints?