Comparison With The Actor Model
In as much as it is concerned with concurrent processes that exchange messages, the Actor model is broadly similar to CSP. However, the two models make some fundamentally different choices with regard to the primitives they provide:
- CSP processes are anonymous, while actors have identities.
- CSP message-passing fundamentally involves a rendezvous between the processes involved in sending and receiving the message, i.e. the sender cannot transmit a message until the receiver is ready to accept it. In contrast, message-passing in actor systems is fundamentally asynchronous, i.e. message transmission and reception do not have to happen at same time, and senders may transmit messages before receivers are ready to accept them. These approaches may be considered duals of each other, in the sense that rendezvous-based systems can be used to construct buffered communications that behave as asynchronous messaging systems, while asynchronous systems can be used to construct rendezvous-style communications by using a message/acknowledgement protocol to synchronize senders and receivers.
- CSP uses explicit channels for message passing, whereas actor systems transmit messages to named destination actors. These approaches may also be considered duals of each other, in the sense that processes receiving through a single channel effectively have an identity corresponding to that channel, while the name-based coupling between actors may be broken by constructing actors that behave as channels.
Read more about this topic: Communicating Sequential Processes
Famous quotes containing the words comparison with the, comparison with, comparison, actor and/or model:
“[Girls] study under the paralyzing idea that their acquirements cannot be brought into practical use. They may subserve the purposes of promoting individual domestic pleasure and social enjoyment in conversation, but what are they in comparison with the grand stimulation of independence and self- reliance, of the capability of contributing to the comfort and happiness of those whom they love as their own souls?”
—Sarah M. Grimke (17921873)
“What is man in nature? A nothing in comparison with the infinite, an all in comparison with the nothinga mean between nothing and everything.”
—Blaise Pascal (16231662)
“But the best read naturalist who lends an entire and devout attention to truth, will see that there remains much to learn of his relation to the world, and that it is not to be learned by any addition or subtraction or other comparison of known quantities, but is arrived at by untaught sallies of the spirit, by a continual self-recovery, and by entire humility.”
—Ralph Waldo Emerson (18031882)
“An actor rides in a bus or railroad train; he sees a movement and applies it to a new role. A woman in agony of spirit might turn her head just so; a man in deep humiliation probably would wring his hands in such a way. From straws like these, drawn from completely different sources, the fabric of a character may be built. The whole garment in which the actor hides himself is made of small externals of observation fitted to his conception of a role.”
—Eleanor Robson Belmont (18781979)
“AIDS occupies such a large part in our awareness because of what it has been taken to represent. It seems the very model of all the catastrophes privileged populations feel await them.”
—Susan Sontag (b. 1933)