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Actor Model Implementation
In computer science, Actor model implementation concerns implementation issues for the Actor model. Cosmic Cube The Caltech Cosmic Cube was developed by Chuck Seitz ''et al.'' at Caltech providing architectural support for Actor systems. A significant difference between the Cosmic Cube and most other parallel processors is that this multiple instruction multiple-data machine uses message passing instead of shared variables for communication between concurrent processes. This computational model is reflected in the hardware structure and operating system, and is also the explicit message passing communication seen by the programmer. According to Seitz 985 :It was a premise of the Cosmic Cube experiment that the internode communication should scale well to very large numbers of nodes. A ''direct'' network like the hypercube satisfies this requirement, with respect to both the aggregate bandwidth achieved across the many concurrent communication channels and the feasibility of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Science
Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical disciplines (including the design and implementation of Computer architecture, hardware and Computer programming, software). Computer science is generally considered an area of research, academic research and distinct from computer programming. Algorithms and data structures are central to computer science. The theory of computation concerns abstract models of computation and general classes of computational problem, problems that can be solved using them. The fields of cryptography and computer security involve studying the means for secure communication and for preventing Vulnerability (computing), security vulnerabilities. Computer graphics (computer science), Computer graphics and computational geometry address the generation of images. Progr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actor Model
The actor model in computer science is a mathematical model of concurrent computation that treats ''actor'' as the universal primitive of concurrent computation. In response to a message it receives, an actor can: make local decisions, create more actors, send more messages, and determine how to respond to the next message received. Actors may modify their own private state, but can only affect each other indirectly through messaging (removing the need for lock-based synchronization). The actor model originated in 1973. It has been used both as a framework for a theoretical understanding of computation and as the theoretical basis for several practical implementations of concurrent systems. The relationship of the model to other work is discussed in actor model and process calculi. History According to Carl Hewitt, unlike previous models of computation, the actor model was inspired by physics, including general relativity and quantum mechanics. It was also influenced by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caltech Cosmic Cube
The Caltech Cosmic Cube was a parallel computer, developed by Charles Seitz and Geoffrey C Fox from 1981 onward. It was the first working hypercube built. It was an early attempt to capitalise on VLSI to speed up scientific calculations at a reasonable cost. Using commodity hardware and an architecture suited to the specific task (QCD), Fox and Seitz demonstrated that this was indeed possible. In 1984 a group at Intel including Justin Rattner and Cleve Moler developed the Intel iPSC inspired by the Cosmic Cube. In 1987 several people in the group formed a company called Parasoft Parasoft (officially Parasoft Corporation) is an independent software vendor specializing in automated software testing and application security with headquarters in Monrovia, California. It was founded in 1987 by four graduates of the Californ ... to commercialize the message passing interface developed for the Cosmic Cube. Characteristics * 64 Intel 8086/87 processors * 128kB of memory per proces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypercube
In geometry, a hypercube is an ''n''-dimensional analogue of a square () and a cube (). It is a closed, compact, convex figure whose 1- skeleton consists of groups of opposite parallel line segments aligned in each of the space's dimensions, perpendicular to each other and of the same length. A unit hypercube's longest diagonal in ''n'' dimensions is equal to \sqrt. An ''n''-dimensional hypercube is more commonly referred to as an ''n''-cube or sometimes as an ''n''-dimensional cube. The term measure polytope (originally from Elte, 1912) is also used, notably in the work of H. S. M. Coxeter who also labels the hypercubes the γn polytopes. The hypercube is the special case of a hyperrectangle (also called an ''n-orthotope''). A ''unit hypercube'' is a hypercube whose side has length one unit. Often, the hypercube whose corners (or ''vertices'') are the 2''n'' points in R''n'' with each coordinate equal to 0 or 1 is called ''the'' unit hypercube. Construction A hyp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Banyan Switch
In electronics, a banyan switch is a complex crossover switch used in electrical or optical switches. It is named for its resemblance to the roots of the banyan tree which cross over in complex patterns. Logical banyan switches are used in logic or signal pathways to crossover switching of signals onto new pathways. They can be mechanical microelectromechanical systems, electrical or nonlinear optics. Their complexity depends on the topology of the individual switches in a switch matrix (how wide it is by how many 'plies' or layers of switches it takes), to implement a desired crossover logic. Design Typical crossover matrices follow this formula: an N×N banyan switch uses (N/2) log2 N elements. Other formulas are used for differing number of crossover layers, and scaling is possible, but becomes very large and complex with large N×N arrays. CAD can be used to take the drudgery out of creating these designs. A banyan network is implemented by interconnecting 2×2 switching ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J–Machine
The J–Machine (Jellybean-Machine) was a parallel computer designed by the MIT Concurrent VLSI Architecture group in conjunction with the Intel Corporation. The machine used "jellybean" parts—cheap and multitudinous commodity parts, each with a processor, memory, and a fast communication interface—and a novel network interface to implement fine grained parallel programs. History The J-machine project was started in 1988 based on work in Bill Dally's doctoral work at Caltech. The philosophy of the work was "processors are cheap and memory is expensive," the ''J'' in the project's title standing for jellybean which are small cheap candies. In order to make use of large numbers of processors, the machine featured a novel network interface using message passing. This allowed a node to send a message to any other node within 2 microseconds. Three 1024-node J-machine systems have been built and are kept at MIT, Caltech and Argonne National Laboratory Argonne National Laborat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bill Dally
William James Dally (born August 17, 1960) is an American computer scientist and educator. Since 2021, he has been a member of the President’s Council of Advisors on Science and Technology (PCAST). Microelectronics He developed a number of techniques used in modern interconnection networks including routing-based deadlock avoidance, wormhole routing, link-level retry, virtual channels, global adaptive routing, and high-radix routers. He has developed efficient mechanisms for communication, synchronization, and naming in parallel computers including message-driven computing and fast capability-based addressing. He has developed a number of stream processors starting in 1995 including Imagine, for graphics, signal, and Image processing, and Merrimac, for scientific computing. He has published over 200 papers as well as the textbooks "Digital Systems Engineering" with John Poulton, and "Principles and Practices of Interconnection Networks" with Brian Towles. He was inventor or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actor Model And Process Calculi
In computer science, the Actor model and process calculi are two closely related approaches to the modelling of concurrent digital computation. See Actor model and process calculi history. There are many similarities between the two approaches, but also several differences (some philosophical, some technical): *There is only one Actor model (although it has numerous formal systems for design, analysis, verification, modeling, ''etc.''); there are numerous process calculi, developed for reasoning about a variety of different kinds of concurrent systems at various levels of detail (including calculi that incorporate time, stochastic transitions, or constructs specific to application areas such as security analysis). *The Actor model was inspired by the laws of physics and depends on them for its fundamental axioms, ''i.e.'' physical laws (see Actor model theory); the process calculi were originally inspired by algebra . *Processes in the process calculi are anonymous, and commun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actor Model Theory
In theoretical computer science, Actor model theory concerns theoretical issues for the Actor model. Actors are the primitives that form the basis of the Actor model 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 designate how to respond to the next message received. Actor model theory incorporates theories of the events and structures of Actor computations, their proof theory, and denotational models. Events and their orderings From the definition of an Actor, it can be seen that numerous events take place: local decisions, creating Actors, sending messages, receiving messages, and designating how to respond to the next message received. However, this article focuses on just those events that are the arrival of a message sent to an Actor. This article reports on the results published in Hewitt 006 :''Law of Countability'': There are at most countably many events. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Baker (computer Scientist)
Henry Givens Baker Jr. is an American computer scientist who has made contributions in garbage collection, functional programming languages, and linear logic. He was one of the founders of Symbolics, a company that designed and manufactured a line of Lisp machines. In 2006 he was recognized as a Distinguished Scientist by the Association for Computing Machinery. He is notable for his research in garbage collection, particularly Baker's real-time copying collector, and on the Actor model. Baker received his B.Sc. (1969), S.M. (1973), E.E. (1973), and Ph.D. (1978) degrees at M.I.T. The Chicken Scheme compiler Chicken (stylized as CHICKEN) is a programming language, specifically a compiler and interpreter which implement a dialect of the programming language Scheme, and which compiles Scheme source code to standard C. It is mostly R5RS compliant an ... was inspired by an innovative design of Baker's. Bibliography * * * * * References External links Henry Baker's Archive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Akinori Yonezawa
is a Japanese computer scientist specializing in object-oriented programming, distributed computing and information security. Being a graduate of the University of Tokyo, Yonezawa has a Ph.D in computer science from MIT in the Actor group at the MIT AI Lab. He currently teaches at the University of Tokyo. He is the designer of ABCL/R, a reflective subset of the first concurrent object-oriented programming language ABCL/1. In November 2009, he was awarded with a Medal of Honour with purple ribbon by the Government of Japan. ''Mainichi Shimbun.'' November 2, 2009 (japanese). He won the Senior |
