This reads like a Ted Dziuba performance art project.<p>I mean designing your setup as a ~15 server cluster <i>on one box</i>? <i></i>on a raid-1 of sata drives!?!<i></i> then xfs on raid-0!!!<p>This url is getting saved now as my canonical 'overengineering leads to faceplants' example.
RabbitMQ if deployed in the wrong manner, or stuck in the wrong place for the wrong reasons will bite you. I see that it looks like a transaction manager because Mongo can't handle tx very well? I beleive MySQL does, and so and Cassandra. Seems more a fit for that type of job.