HN Reader

Please change the title to the original, "Actors: A Model Of Concurrent Computation In Distributed Systems".

I'm not normally a stickler for HN's rule about title preservation, but in this case the "in distributed systems" part is crucial, because IMO the urge to use both the actor model (and its relative, CSP) in non-distributed systems solely in order to achieve concurrency has been a massive boondoggle and a huge dead end. Which is to say, if you're within a single process, what you want is structured concurrency ( https://vorpus.org/blog/notes-on-structured-concurrency-or-g... ), not the unstructured concurrency that is inherent to a distributed system.

A more legible version: https://dspace.mit.edu/handle/1721.1/6952

https://en.wikipedia.org/wiki/Gul_Agha_(computer_scientist)

It doesn't feel 1985. Feels very 2015. Really good insights. Remembering the hardware they had back then too, and ~14 years before Google took off.

I think Microsoft Orleans, Erlang OTP and Scala Play are probably most famous examples in use today.

> It captures the nondeterminism in the order of delivery of communications. The Subsequent transition captures fairness arising from the guarantee of delivery. We provide a denotational semantics for our minimal actor language in terms of the transition relations.

Juicy paper, not to mention the declassification. It really reminds me of asyncmachine.dev which has actors, relations, transitions, and embraces non-determinism.

Missing: (1985)

Actor model is one of these things that really seduces me on paper, but my only exposure to it was in my consulting career, and that was to help migrate away from it. The use case seemed particularly adapted (integration of a bunch of remote devices with spotty connection), but it was practically a nightmare to debug... which was a problem since it was buggy.

To be fair, the problem was probably that particular implementation, but I'm wondering if there's any successful rollout of that model at any significant scale out there.

May be of interest: Pony Language is designed from the ground up to support the Actor model.

https://www.ponylang.io/

> It is generally believed that the next generation of computers will involve massively parallel architectures.

To this day - we have only taken advantage of parallel architectures in GPUs - a lot of software still runs on single CPU threads. most programming languages- are made optimized for single threads - yeah we might have threads, virtual threads, fibers etc - but how many people are using those on a daily basis?