Re: [Haskell-cafe] Best Actor system?

I don't actually want to get drawn into this, but one point would be that it's really just the same fallacies as OOP in general, but concurrent. The idea that isolation behind an interface (message passing or not) is going to prevent unnecessary mutation or side effects from getting out of control. In practice, it doesn't do that at all and the fact that you're making your inter-dependencies more implicit, rather than explicit, through the use of isolated buckets of side-effecting state and mutation is going to make it harder rather than easier to debug the program when it invariably breaks. I'd rather get a call-stack if I'm going to abandon Haskell-y goodness. And your Actors *will* get into a bad state, so you'll end up writing Inspector and Debugger mixins just to keep a handle on the complexity when they get into that bad state. It's not impossible for Actors to make sense. I used agents (which are not full-blown Actors per se) in Clojure for side-effect isolation, serialization, and thread safety to good effect, but I kept how much "work" they did to a bare minimum and tried to keep everything in pure functions as long as I could. It's just that I see programmers with a shiny new hammer looking for every nail they can find. On Thu, Mar 27, 2014 at 12:21 PM, Zongheng Yang wrote:

Can anyone give some detailed cons of Akka / actor model?

On Thu, Mar 27, 2014 at 5:21 AM, Alois Cochard wrote:

...

I have good experience with actors (Scala/Akka), and I can tell you that you should avoid them as much as possible. I think the model is good if you need to do some low level concurrency coding on a language that don't have effect tracking in types.

Having used the Async library from Marlow, I highly recommend it... and it probably cover a big percentage of traditional concurrency use cases.

You still have Haskell Cloud if you want distributed messaging.

Cheers

On 27 March 2014 06:29, james wrote:

...

Having been introduced to actors by looking at Erlang, I discovered

Akka.

...

It seems that the performance is pretty impressive and I like the model.

There seem to be several basic Actor libraries in Hackage, but they

don't

...

seem to be very actively developed.

I'm more interested in the model for programming within a single runtime than I am for distributed systems, but message and dispatch performance definitely is important.

Can anyone share experiences with the different packages? Is any one of them stand-out?

Thanks James

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