Hello Bill, You wrote:
> - load balancing. Anyone here know how to build out an XMPP > deployment that has hundreds of thousands to low millions of users, > never mind 50M+? Yes, we know several of them. > - clustering. Fwiw, I don't think it's easy enough to cluster XMPP > servers compared to web farms. Generic Tools like pound/perlbal mostly > don't exist in the XMPP world. The OSS stacks I've seen, ejabberd, > openfire, jabberd2 are limited to what I'd call "lan scale". To work > with long lived connections at this scale you have to be using epoll. XMPP can be improved. Some improvements will need to be made in protocol other in implementation. You have a large progress margin to web scale. However, XMPP is definitely not "lan scale". To my knowledge the current limit being worked on is for deployments over a single domain covering tens of millions of users and several millions of simultaneous users. You can reach this limit with XMPP and there is web community that need this kind of scale (Facebook being one), but there is a vast majority for which XMPP is perfectly suitable today in term of scale. My last comment is that the problem you have to deal with is inherent to the functional requirement in most case. XMPP is only a transport in most case. If the requirements of the application is to distribute millions of copy of a presence packet for example, you have to distribute them no matter the technology you use. -- Mickaël Rémond http://www.process-one.net/
