JMS and Scala actors share a theoretical similarity but don’t think of them as necessarily solving the same problems architecturally. Actors are meant to be a lightweight alternative to shared-memory concurrency where races and deadlocks are generally harder to accidentally create. JMS is a sophisticated API that’s meant to span direct messaging, publish/subscribe, transactions, EJB … Read more
The actor model operates on message passing. Individual processes (actors) are allowed to send messages asynchronously to each other. What distinguishes this from what we normally think of as the threading model, is that there is (in theory at least) no shared state. And if one believes (justifiably, I think) that shared state is the … Read more
Without going into the details (about which I know too little in the case of Node.js), the main difference is that Node.js supports only concurrency without parallelism while Akka supports both. Both systems are completely event-driven and can scale to large work-loads, but the lack of parallelism makes it difficult in Node.js (i.e. parallelism is … Read more
First, each actor waiting on receive is occupying a thread. If it never receives anything, that thread will never do anything. An actor on react does not occupy any thread until it receives something. Once it receives something, a thread gets allocated to it, and it is initialized in it. Now, the initialization part is … Read more
First off the “older” message systems (MQ) are older in implementation but they are a newer in engineering idea of: transactional persistent queues. Scala Actors and Akka maybe a newer implementation but are built on an older concurrency model of Actors. The two models however end up being very similar in practice because they both … Read more
The Google Code project does reference a technical paper on the implementation of the ring buffer, however it is a bit dry, academic and tough going for someone wanting to learn how it works. However there are some blog posts that have started to explain the internals in a more readable way. There is an … Read more