I'm trying to get my head around AMQP. It looks great for inter-machine (cluster, LAN, WAN) communication between applications but I'm not sure if it is suitable (in architectural, and current implementation terms) for use as a software bus within one machine.
Would it be worth pulling out a current high performance message passing framework to replace it with AMQP, or is this falling into the same trap as RPC by blurring the distinction between local and non-local communication?
I'm also wary of the performance impacts of using a WAN technology for intra-machine communications, although this may be more of an implementation concern than architecture.
War stories would be appreciated.
AMQP is not an RPC framework. It provides the building blocks to model things like shared queues, RPC, pubsub etc. but it does not mandate any specific way to use it.
If you want to partition your application (making it distributable on the way) and to wire it together with AMQP I think it's the right technology. There might be faster alternatives though but probably none as generic as AMQP.