Actor model middle history
Encyclopedia
In computer science
, the Actor model
, first published in 1973 , is a mathematical model of concurrent computation. This article reports on the middle history of the Actor model in which major themes were initial implementations, initial applications, and development of the first proof theory and denotational model. It is the follow on article to Actor model early history
which reports on the early history of the Actor model which concerned the basic development of the concepts. The article Actor model later history
reports on developments after the ones reported in this article.
[1974] published the principle of Actor induction which is:
In his doctoral dissertation, Aki Yonezawa developed further techniques for proving properties of Actor systems including those that make use of migration. Russ Atkinson and Carl Hewitt developed techniques for proving properties of Serializers that are guardians of shared resources. Gerry Barber's doctoral disseration concerned reasoning about change in knowledgeable office systems.
(the automatic reclamation of unused storage) was an important theme in the development of the Actor model.
In his doctoral dissertation, Peter Bishop developed an algorithm for garbage collection in distributed systems. Each system kept lists of links of pointers to and from other systems. Cyclic structures were collected by incrementally migrating Actors (objects) onto other systems which had their addresses until a cyclic structure was entirely contained in a single system where the garbage collector could recover the storage.
Henry Baker
developed an algorithm for real-time garbage collection in his doctoral dissertation. The fundamental idea was to interleave collection activity with construction activity so that there would not have to be long pauses while collection takes place. See incremental garbage collection.
Henry Lieberman and Carl Hewitt [1983] developed a real time garbage collection based on the lifetimes of Actors (Objects). The fundamental idea was to allocate Actors (objects) in generations so that only the latest generations would have to be examined during a garbage collection. See generational garbage collection.
in his doctoral disseration. William Athas and Nanette Boden [1988] developed Cantor which is an Actor programming language for scientific computing. Jean-Pierre Briot [1988, 1999] developed means to extend Smalltalk 80 for Actor computations. Christine Tomlinson, Mark Scheevel, Greg Lavender, Greg Meredith, et al. [1995] at MCC developed an Actor programming language for InfoSleuth agents in Rosette.
Carl Hewitt, Beppe Attardi, and Henry Lieberman [1979] developed proposals for delegation in message passing. This gave rise to the so-called inheritance anomaly controversy in object-oriented concurrent programming languages [Satoshi Matsuoka and Aki Yonezawa 1993, Giuseppe Milicia and Vladimiro Sassone 2004].
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Computer science
Computer science or computing science is the study of the theoretical foundations of information and computation and of practical techniques for their implementation and application in computer systems...
, the Actor model
Actor model
In computer science, the Actor model is a mathematical model of concurrent computation that treats "actors" as the universal primitives of concurrent digital computation: in response to a message that it receives, an actor can make local decisions, create more actors, send more messages, and...
, first published in 1973 , is a mathematical model of concurrent computation. This article reports on the middle history of the Actor model in which major themes were initial implementations, initial applications, and development of the first proof theory and denotational model. It is the follow on article to Actor model early history
Actor model early history
In computer science, the Actor model, first published in 1973 , is a mathematical model of concurrent computation. This article is about the early history of the Actor model...
which reports on the early history of the Actor model which concerned the basic development of the concepts. The article Actor model later history
Actor model later history
In computer science, the Actor model, first published in 1973 , is a mathematical model of concurrent computation. This article reports on the later history of the Actor model in which major themes were investigation of the basic power of the model, study of issues of compositionality, development...
reports on developments after the ones reported in this article.
Proving properties of Actor systems
Carl HewittCarl Hewitt
Carl Hewitt is Board Chair of the International Society for Inconsistency Robustness. He has been a Visiting Professor at Stanford University and the University of Keio. In 2000, he became emeritus in the EECS department at MIT....
[1974] published the principle of Actor induction which is:
- Suppose that an Actor x has property P when it is created
- Further suppose that if x has property P when it processes a message, then it has property P when it processes the next message.
- Then x always has the property P.
In his doctoral dissertation, Aki Yonezawa developed further techniques for proving properties of Actor systems including those that make use of migration. Russ Atkinson and Carl Hewitt developed techniques for proving properties of Serializers that are guardians of shared resources. Gerry Barber's doctoral disseration concerned reasoning about change in knowledgeable office systems.
Garbage Collection
Garbage collectionGarbage collection (computer science)
In computer science, garbage collection is a form of automatic memory management. The garbage collector, or just collector, attempts to reclaim garbage, or memory occupied by objects that are no longer in use by the program...
(the automatic reclamation of unused storage) was an important theme in the development of the Actor model.
In his doctoral dissertation, Peter Bishop developed an algorithm for garbage collection in distributed systems. Each system kept lists of links of pointers to and from other systems. Cyclic structures were collected by incrementally migrating Actors (objects) onto other systems which had their addresses until a cyclic structure was entirely contained in a single system where the garbage collector could recover the storage.
Henry Baker
Henry Baker (computer scientist)
Henry Givens Baker Jr. is a computer scientist who has made contributions in garbage collection, functional programming languages, and linear logic. He was also one of the founders of Symbolics...
developed an algorithm for real-time garbage collection in his doctoral dissertation. The fundamental idea was to interleave collection activity with construction activity so that there would not have to be long pauses while collection takes place. See incremental garbage collection.
Henry Lieberman and Carl Hewitt [1983] developed a real time garbage collection based on the lifetimes of Actors (Objects). The fundamental idea was to allocate Actors (objects) in generations so that only the latest generations would have to be examined during a garbage collection. See generational garbage collection.
Actor programming languages
Henry Lieberman, Dan Theriault, et al. developed Act1, an Actor programming language. Subsequently for his masters thesis, Dan Theriault developed Act2. These early proof of concept languages were rather inefficient and not suitable for applications. In his doctoral dissertation, Ken Kahn developed Ani, which he used to develop several animations. Bill Kornfeld developed the Ether programming language for the Scientific Community MetaphorScientific community metaphor
In computer science, the Scientific Community Metaphor is a metaphor used to aid understanding scientific communities. The first publications on the Scientific Community Metaphor in 1981 and 1982 involved the development of a programming language named Ether that invoked procedural plans to...
in his doctoral disseration. William Athas and Nanette Boden [1988] developed Cantor which is an Actor programming language for scientific computing. Jean-Pierre Briot [1988, 1999] developed means to extend Smalltalk 80 for Actor computations. Christine Tomlinson, Mark Scheevel, Greg Lavender, Greg Meredith, et al. [1995] at MCC developed an Actor programming language for InfoSleuth agents in Rosette.
Carl Hewitt, Beppe Attardi, and Henry Lieberman [1979] developed proposals for delegation in message passing. This gave rise to the so-called inheritance anomaly controversy in object-oriented concurrent programming languages [Satoshi Matsuoka and Aki Yonezawa 1993, Giuseppe Milicia and Vladimiro Sassone 2004].
A denotational model of Actor systems
In his doctoral dissertation, Will Clinger developed the first denotational model of Actor systems. See denotational semantics of the Actor modelDenotational semantics of the Actor model
The denotational semantics of the Actor model is the subject of denotational domain theory for Actors. The historical development of this subject is recounted in [Hewitt 2008b].-Actor fixed point semantics:...
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