actoragentfaas

Does it make sense to use actor/agent oriented programming in Function as a Service environment?

I am wondering, if is it possible to apply agent/actor library (Akka, Orbit, Quasar, JADE, Reactors.io) in Function as a Service environment (OpenWhisk, AWS Lambda)?

Does it make sense?

If yes, what is minimal example hat presents added value (that is missing when we are using only FaaS or only actor/agent library)?

If no, then are we able to construct decision graph, that can help us decide, if for our problem should we use actor/agent library or FaaS (or something else)?

Solution

  • This is more opinion based question, but I think, that in the current shape there's no sense in putting actors into FaaS - opposite works actually quite well: OpenWhisk is implemented on top of Akka actually.

    There are several reasons:

    1. FaaS current form is inherently stateless, which greatly simplifies things like request routing. Actors are stateful by nature.
    2. From my experience FaaS functions are usually disjointed - ofc you need some external resources, but this is the mental model: generic resources and capabilities. In actor models we tend to think in category of particular entities represented as actors i.e. user Max, rather than table of users. I'm not covering here the scope of using actors solely as unit of concurrency.
    3. FaaS applications have very short lifespan - this is one of the founding stones behind them. Since creation, placement and state recovery for more complex actors may take a while, and you usually need a lot of them to perform a single task, you may end up at point when restoring the state of a system takes more time than actually performing the task, that state is needed for.

    That being said, it's possible that in the future, those two approaches will eventually converge, but it needs to be followed with changes in both mental and infrastructural model (i.e. actors live in runtime, which FaaS must be aware of). IMO setting up existing actor frameworks on top of existing FaaS providers is not feasible at this point.