There are a couple of types of distributed applications though, right?
There's the traditional client/server scenario where you distribute the load horizontally across many servers. If most of the server computation is stateless, and all the state is stored in the database, then you can use either the FaaS or the actor model.
Then there's the client/server scenario where the server computation is stateful, in which case you shouldn't use FaaS. You could still use actors though. Isn't this where Orleans sits?
Then there's the peer to peer architecture where all computers run the same code, whether they're in the cloud or on an end user's laptop or phone. Does Orleans make sense in this case?
Case 2 is the most popular one.
Sometimes people migrate from Case 1 when they start hitting performance bottlenecks of hitting database on every request or/and experience congestions from uncoordinated concurrent writes.
Orleans doesn't make a lot of sense for Case 3 IMO. Peer-to-peer is not a good environment for forming stable clusters and making resource management decision the way the are done in the traditional server-side case.
There's the traditional client/server scenario where you distribute the load horizontally across many servers. If most of the server computation is stateless, and all the state is stored in the database, then you can use either the FaaS or the actor model.
Then there's the client/server scenario where the server computation is stateful, in which case you shouldn't use FaaS. You could still use actors though. Isn't this where Orleans sits?
Then there's the peer to peer architecture where all computers run the same code, whether they're in the cloud or on an end user's laptop or phone. Does Orleans make sense in this case?