I've been looking at akka recently and it's pretty impressive. It looks like it has most of the killer features of erlang - location transparency, supervision hierarchies, and more. Are there any features erlang has that akka doesn't?
Answer
Disclaimer: I am the PO for Akka
- Erlang does copy-on-send - Akka uses shared memory (immutable objects) for in-VM sends
- Erlang does per-process GC - Akka uses JVM GCs
- Erlang has OTP - Akka integrates with the entire Java ecosystem (Apache Camel, JAX-RS, etc etc)
- Erlang does the process scheduling for you - Akka allows you to use many different Dispatchers with endless configuration opportunities
- Erlang does hot code reload - Akka can support it, but it's less flexible because of JVM classloading
Those are the ones from the top of my head.
On the other hand, using Akka means that you can use Scala, Java, Groovy or JRuby to write your applications.