I’m confused by your choice of three terms to compare. Within RabbitMQ, Fanout and Direct are exchange types. Pub-Sub is a generic messaging pattern but not an exchange type. And you didn’t even mention the 3rd and most important Exchange type, namely Topic. In fact, you can implement Fanout behavior on a Topic exchange just … Read more
The message bus implies a common protocol spoken and understood by all participants. There is little to no logic in the bus. Usually the message is forwarded to all connected systems. The hub-and-spoke architecture (or “message broker”) has a central piece of software which understands the messages sent to it, can translate them, and forward … Read more
ActiveMQ is a message broker which implements the JMS API and supports a number of cross language clients and network protocols. It lets you implement queues or topics and write listeners or subscribers to respond to queue events. Mule and ServiceMix are open source ESB (enterprise service bus). An ESB has capabilities beyond JMS: queuing … Read more
I think you have several issues with initial understanding. Frankly, I’m a bit surprised to see the following: both need 5 threads to handle the volume. How did you identify you need that exact number? Do you have any guarantees 5 threads will be enough? RabbitMQ is tuned and time tested, so it is all … Read more
The difference is that a PUB socket sends the same message to all subscribers, whereas PUSH does a round-robin amongst all its connected PULL sockets. In your example, if you send just a single message from the root, then all the subscribers will receive it (barring slow subscribers, etc.) but only 1 worker. The pub/sub … Read more
async req / res communication (inproc or remote) between nodes Both libraries allow for synchronous or asynchronous communication depending on how to implement the communication. See this page for gRPC: http://www.grpc.io/docs/guides/concepts.html. Basically gRPC allow for typical HTTP synchronous request/response or a ‘websocket-like’ bidirectional streaming. For 0mq you can setup a simple REQ-REP connection which is … Read more
JMS and messaging is really about 2 totally different things. publish and subscribe (sending a message to as many consumers as are interested – a bit like sending an email to a mailing list, the sender does not need to know who is subscribed high performance reliable load balancing (message queues) See more info on … Read more
You can try something like SEL s = NSSelectorFromString(selectorName); [anObject performSelector:s];
what makes them better than writing your own library? When rolling out the first version of your app, probably nothing: your needs are well defined and you will develop a messaging system that will fit your needs: small feature list, small source code etc. Those tools are very useful after the first release, when you … Read more
NServiceBus is growing in popularity. It is open source as well. Here is a Hanselminutes episode with Scott Hanselman talking with Udi Dahan about NServiceBus to help grok it. You should definitely evaluate using it. UPDATE: There’s also a DNR TV episode which shows what it’s like to build an NServiceBus solution from scratch here: … Read more