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SISAL (Italy)
SISAL (Streams and Iteration in a Single Assignment Language) is a general-purpose single assignment functional programming language with strict semantics, implicit parallelism, and efficient array handling. SISAL outputs a dataflow graph in Intermediary Form 1 (IF1). It was derived from VAL (Value-oriented Algorithmic Language, designed by Jack Dennis), and adds recursion and finite streams. It has a Pascal-like syntax and was designed to be a common high-level language for numerical programs on a variety of multiprocessors. History SISAL was defined in 1983 by James McGraw et al., at the University of Manchester, LLNL, Colorado State University and DEC. It was revised in 1985, and the first compiled implementation was made in 1986. Its performance is superior to C and rivals Fortran, according to some sources,Retire Fortran?: a debate rekindled, David Cann, August 1992, Communications of the ACM, Volume 35, Issue 8 combined with efficient and automatic parallelization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Functional Programming
In computer science, functional programming is a programming paradigm where programs are constructed by applying and composing functions. It is a declarative programming paradigm in which function definitions are trees of expressions that map values to other values, rather than a sequence of imperative statements which update the running state of the program. In functional programming, functions are treated as first-class citizens, meaning that they can be bound to names (including local identifiers), passed as arguments, and returned from other functions, just as any other data type can. This allows programs to be written in a declarative and composable style, where small functions are combined in a modular manner. Functional programming is sometimes treated as synonymous with purely functional programming, a subset of functional programming which treats all functions as deterministic mathematical functions, or pure functions. When a pure function is call ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jack Dennis
Jack Bonnell Dennis (born October 13, 1931) is a computer scientist and Emeritus Professor of Computer Science and Engineering at Massachusetts Institute of Technology. The work of Dennis in computer systems and computer languages is recognized to have played a key role in hacker culture. As a Massachusetts Institute of Technology faculty member he sponsored easier access to computer facilities at MIT during the early development of the subculture. Much of what would later become Unix came from his early collaboration with Dennis Ritchie and Ken Thompson. This collaborative and open philosophy lives on today. Dennis was also a member of the historic Tech Model Railroad Club, which incubated much of the early slang and traditions of hacking. Early life and education Dennis graduated from the Massachusetts Institute of Technology (MIT) as Bachelor of Science (1953), Master of Science (1954), and Doctor of Science (1958). His doctoral thesis analyzed the relation between m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granularity
Granularity (also called graininess), the condition of existing in granules or grains, refers to the extent to which a material or system is composed of distinguishable pieces. It can either refer to the extent to which a larger entity is subdivided, or the extent to which groups of smaller indistinguishable entities have joined together to become larger distinguishable entities. Precision and ambiguity Coarse-grained materials or systems have fewer, larger discrete components than fine-grained materials or systems. * A coarse-grained description of a system regards large subcomponents. * A fine-grained description regards smaller components of which the larger ones are composed. The concepts granularity, coarseness, and fineness are relative; and are used when comparing systems or descriptions of systems. An example of increasingly fine granularity: a list of nations in the United Nations, a list of all states/provinces in those nations, a list of all cities in those states ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systolic Array
In parallel computer architectures, a systolic array is a homogeneous network of tightly coupled data processing units (DPUs) called cells or nodes. Each node or DPU independently computes a partial result as a function of the data received from its upstream neighbours, stores the result within itself and passes it downstream. Systolic arrays were first used in Colossus, which was an early computer used to break German Lorenz ciphers during World War II. Due to the classified nature of Colossus, they were independently invented or rediscovered by H. T. Kung and Charles Leiserson who described arrays for many dense linear algebra computations (matrix product, solving systems of linear equations, LU decomposition, etc.) for banded matrices. Early applications include computing greatest common divisors of integers and polynomials. They are sometimes classified as Multiple instruction, single data, multiple-instruction single-data (MISD) architectures under Flynn's taxonomy, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
INMOS Transputer
The transputer is a series of pioneering microprocessors from the 1980s, intended for parallel computing. To support this, each transputer had its own integrated memory and serial communication links to exchange data with other transputers. They were designed and produced by Inmos, a semiconductor company based in Bristol, United Kingdom. For some time in the late 1980s, many considered the transputer to be the next great design for the future of computing. While the transputer did not achieve this expectation, the transputer architecture was highly influential in provoking new ideas in computer architecture, several of which have re-emerged in different forms in modern systems. Background In the early 1980s, conventional central processing units (CPUs) appeared to have reached a performance limit. Up to that time, manufacturing difficulties limited the amount of circuitry that could fit on a chip. Continued improvements in the fabrication process had largely removed this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encore Computer
Encore Computer was an early pioneer in the parallel computing market, based in Marlborough, Massachusetts. Although offering several system designs beginning in 1985, they were never as well known as other companies in this field such as Pyramid Technology, Alliant, and the most similar systems Sequent and FLEX. Encore was founded in 1983 by: Kenneth Fisher, former CEO of Prime Computer; Gordon Bell, an engineering vice president from Digital Equipment Corporation responsible for the development of the VAX; and, Henry Burkhardt III, co-founder of Data General and Kendall Square Research. Their goal was to build massively parallel machines from commodity processors; their first design, the Multimax, was released in September 1985. This was one of the first commercial designs to make use of bus snooping, allowing many processors to share the same memory efficiently. History In 1988 Encore purchased the former Systems Engineering Laboratories (SEL) from Nippon Mining. SEL, f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sequent Computer Systems
Sequent Computer Systems was a computer company that designed and manufactured multiprocessing computer systems. They were among the pioneers in high-performance symmetric multiprocessing (SMP) open systems, innovating in both hardware (e.g., cache management and interrupt handling) and software (e.g., read-copy-update). Through a partnership with Oracle Corporation, Sequent became a dominant high-end UNIX platform in the late 1980s and early 1990s. Later they introduced a next-generation high-end platform for UNIX and Windows NT based on a non-uniform memory access architecture, NUMA-Q. As hardware prices fell in the late 1990s, and Intel shifted their server focus to the Itanium processor family, Sequent joined the Project Monterey effort in October 1998. which aimed to move a standard Unix to several new platforms. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cray-2
The Cray-2 is a supercomputer with four vector processors made by Cray Research starting in 1985. At 1.9 GFLOPS peak performance, it was the fastest machine in the world when it was released, replacing the Cray X-MP in that spot. It was, in turn, replaced in that spot by the Cray Y-MP in 1988. The Cray-2 was the first of Seymour Cray's designs to successfully use multiple CPUs. This had been attempted in the CDC 8600 in the early 1970s, but the emitter-coupled logic (ECL) transistors of the era were too difficult to package into a working machine. The Cray-2 addressed this through the use of ECL integrated circuits, packing them in a novel 3D wiring that greatly increased circuit density. The dense packaging and resulting heat loads were a major problem for the Cray-2. This was solved in a unique fashion by forcing the electrically inert Fluorinert liquid through the circuitry under pressure and then cooling it outside the processor box. The unique "waterfall" cooler syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cray Y-MP
The Cray Y-MP was a supercomputer sold by Cray Research from 1988, and the successor to the company's X-MP. The Y-MP retained software compatibility with the X-MP, but extended the address registers from 24 to 32 bits. High-density VLSI ECL technology was used and a new liquid-cooling system was devised. The Y-MP ran the Cray UNICOS operating system. The Y-MP could be equipped with two, four or eight vector processors, with two functional units each and a clock cycle time of 6 ns (167 MHz). Peak performance was thus 333 megaflops per processor. Main memory comprised 128, 256 or 512 MB of SRAM. The original Y-MP (otherwise known as the Y-MP Model D) was housed in a chassis similar to the horseshoe-shaped X-MP, but with an extra rectangular cabinet added in the middle (containing the CPU boards), thus forming a "Y" shape in plan view. The system could be configured with one or two ''Model D'' IOSs (Input/Output Subsystems) and an optional Solid State Disk (SSD) of 256 M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cray X-MP
The Cray X-MP was a supercomputer designed, built and sold by Cray Research. It was announced in 1982 as the "cleaned up" successor to the 1975 Cray-1, and was the world's fastest computer from 1983 to 1985 with a quad-processor system performance of 800 MFLOPS. The principal designer was Steve Chen. Description The X-MP's main improvement over the Cray-1 was that it was a shared-memory parallel vector processor, the first such computer from Cray Research. It housed up to four CPUs in a mainframe that was nearly identical in outside appearance to the Cray-1. The X-MP CPU had a faster 9.5 nanosecond clock cycle (105 MHz), compared to 12.5 ns for the Cray-1A. It was built from bipolar gate-array integrated circuits containing 16 emitter-coupled logic gates each. The CPU was very similar to the Cray-1 CPU in architecture, but had better memory bandwidth (with two read ports and one write port to the main memory instead of only one read/write port) and improved chai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cray
Cray Inc., a subsidiary of Hewlett Packard Enterprise, is an American supercomputer manufacturer headquartered in Seattle, Washington. It also manufactures systems for data storage and analytics. Several Cray supercomputer systems are listed in the TOP500, which ranks the most powerful supercomputers in the world. Cray manufactures its products in part in Chippewa Falls, Wisconsin, where its founder, Seymour Cray, was born and raised. The company also has offices in Bloomington, Minnesota (which have been converted to Hewlett Packard Enterprise offices), and numerous other sales, service, engineering, and R&D locations around the world. The company's predecessor, Cray Research, Inc. (CRI), was founded in 1972 by computer designer Seymour Cray. Seymour Cray later formed Cray Computer Corporation (CCC) in 1989, which went bankrupt in 1995. Cray Research was acquired by Silicon Graphics (SGI) in 1996. Cray Inc. was formed in 2000 when Tera Computer Company purchased the Cray Rese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grep
grep is a command-line utility for searching plain-text data sets for lines that match a regular expression. Its name comes from the ed command ''g/re/p'' (''globally search for a regular expression and print matching lines''), which has the same effect. grep was originally developed for the Unix operating system, but later available for all Unix-like systems and some others such as OS-9. History Before it was named, grep was a private utility written by Ken Thompson to search files for certain patterns. Doug McIlroy, unaware of its existence, asked Thompson to write such a program. Responding that he would think about such a utility overnight, Thompson actually corrected bugs and made improvements for about an hour on his own program called s (short for "search"). The next day he presented the program to McIlroy, who said it was exactly what he wanted. Thompson's account may explain the belief that grep was written overnight. Thompson wrote the first version in PDP-11 asse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
