1.
Unix-like
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A Unix-like operating system is one that behaves in a manner similar to a Unix system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification. A Unix-like application is one that behaves like the corresponding Unix command or shell, there is no standard for defining the term, and some difference of opinion is possible as to the degree to which a given operating system or application is Unix-like. The Open Group owns the UNIX trademark and administers the Single UNIX Specification and they do not approve of the construction Unix-like, and consider it a misuse of their trademark. Other parties frequently treat Unix as a genericized trademark, in 2007, Wayne R. Gray sued to dispute the status of UNIX as a trademark, but lost his case, and lost again on appeal, with the court upholding the trademark and its ownership. Unix-like systems started to appear in the late 1970s and early 1980s, many proprietary versions, such as Idris, UNOS, Coherent, and UniFlex, aimed to provide businesses with the functionality available to academic users of UNIX. These largely displaced the proprietary clones, growing incompatibility among these systems led to the creation of interoperability standards, including POSIX and the Single UNIX Specification. Various free, low-cost, and unrestricted substitutes for UNIX emerged in the 1980s and 1990s, including 4. 4BSD, Linux, some of these have in turn been the basis for commercial Unix-like systems, such as BSD/OS and OS X. The various BSD variants are notable in that they are in fact descendants of UNIX, however, the BSD code base has evolved since then, replacing all of the AT&T code. Since the BSD variants are not certified as compliant with the Single UNIX Specification, dennis Ritchie, one of the original creators of Unix, expressed his opinion that Unix-like systems such as Linux are de facto Unix systems. Eric S. Raymond and Rob Landley have suggested there are three kinds of Unix-like systems, Genetic UNIX Those systems with a historical connection to the AT&T codebase. Most commercial UNIX systems fall into this category, so do the BSD systems, which are descendants of work done at the University of California, Berkeley in the late 1970s and early 1980s. Some of these systems have no original AT&T code but can trace their ancestry to AT&T designs. Trademark or branded UNIX These systems—largely commercial in nature—have been determined by the Open Group to meet the Single UNIX Specification and are allowed to carry the UNIX name, many ancient UNIX systems no longer meet this definition. Around 2001, Linux was given the opportunity to get a certification including free help from the POSIX chair Andrew Josey for the price of one dollar. Some non-Unix-like operating systems provide a Unix-like compatibility layer, with degrees of Unix-like functionality. IBM z/OSs UNIX System Services is sufficiently complete to be certified as trademark UNIX, cygwin and MSYS both provide a GNU environment on top of the Microsoft Windows user API, sufficient for most common open source software to be compiled and run. Subsystem for Unix-based Applications provides Unix-like functionality as a Windows NT subsystem, Windows Subsystem for Linux provides a Linux-compatible kernel interface developed by Microsoft and containing no Linux code, with Ubuntu user-mode binaries running on top of it
2.
Operating system
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An operating system is system software that manages computer hardware and software resources and provides common services for computer programs. All computer programs, excluding firmware, require a system to function. Operating systems are found on many devices that contain a computer – from cellular phones, the dominant desktop operating system is Microsoft Windows with a market share of around 83. 3%. MacOS by Apple Inc. is in place, and the varieties of Linux is in third position. Linux distributions are dominant in the server and supercomputing sectors, other specialized classes of operating systems, such as embedded and real-time systems, exist for many applications. A single-tasking system can run one program at a time. Multi-tasking may be characterized in preemptive and co-operative types, in preemptive multitasking, the operating system slices the CPU time and dedicates a slot to each of the programs. Unix-like operating systems, e. g. Solaris, Linux, cooperative multitasking is achieved by relying on each process to provide time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking, 32-bit versions of both Windows NT and Win9x, used preemptive multi-tasking. Single-user operating systems have no facilities to distinguish users, but may allow multiple programs to run in tandem, a distributed operating system manages a group of distinct computers and makes them appear to be a single computer. The development of networked computers that could be linked and communicate with each other gave rise to distributed computing, distributed computations are carried out on more than one machine. When computers in a work in cooperation, they form a distributed system. The technique is used both in virtualization and cloud computing management, and is common in large server warehouses, embedded operating systems are designed to be used in embedded computer systems. They are designed to operate on small machines like PDAs with less autonomy and they are able to operate with a limited number of resources. They are very compact and extremely efficient by design, Windows CE and Minix 3 are some examples of embedded operating systems. A real-time operating system is a system that guarantees to process events or data by a specific moment in time. A real-time operating system may be single- or multi-tasking, but when multitasking, early computers were built to perform a series of single tasks, like a calculator. Basic operating system features were developed in the 1950s, such as resident monitor functions that could run different programs in succession to speed up processing
3.
Cray
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Cray Inc. is an American supercomputer manufacturer headquartered in Seattle, Washington. It also manufactures systems for storage and analytics. Several Cray supercomputer systems are listed in the TOP500, which ranks the most powerful supercomputers in the world, the number of Cray systems on the list varies from year to year. Cray manufactures its products in Chippewa Falls, Wisconsin, where its founder, Seymour Cray, was born, the company also has offices in St. Paul, Minnesota, and numerous other sales, service, engineering, and R&D locations around the world. The companys predecessor, Cray Research, Inc. was founded in 1972 by computer designer Seymour Cray, Seymour Cray went on to form the spin-off Cray Computer Corporation, in 1989, which went bankrupt in 1995, while Cray Research was bought by SGI the next year. Cray Inc. was formed in 2000 when Tera Computer Company purchased the Cray Research Inc. business from SGI, Seymour Cray began working in the computing field in 1950 when he joined Engineering Research Associates in Saint Paul, Minnesota. There, he helped to create the ERA1103, ERA eventually became part of UNIVAC, and began to be phased out. He left the company in 1960, a few years after former ERA employees set up Control Data Corporation and he initially worked out of the CDC headquarters in Minneapolis, but grew upset by constant interruptions by managers. He eventually set up a lab at his town in Chippewa Falls, Wisconsin. Cray had a string of successes at CDC, including the CDC6600, copying the previous arrangement, Cray kept the research and development facilities in Chippewa Falls, and the business headquarters in Minneapolis. The companys first product, the Cray-1 supercomputer, was a success because it was faster than all other computers at the time. The first system was sold within a month for US$8.8 million, Seymour Cray continued working, this time on the Cray-2, though it only ended up being marginally faster than the Cray X-MP, developed by another team at the company. Cray soon left the CEO position to become an independent contractor, however, the changing political climate resulted in poor sales prospects. Ultimately, only one Cray-3 was delivered, and a number of designs were never completed. The company filed for bankruptcy in 1995, cCCs remains then began Crays final corporation, SRC Computers, Inc. which still exists. Cray Research continued development along a line of computers, originally with lead designer Steve Chen. The uncertainty of the Cray-2 project gave rise to a number of Cray-object-code compatible Crayette firms, Scientific Computer Systems, American Supercomputer, Supertek, most sites with a Cray installation were considered a member of the exclusive club of Cray operators. Cray computers were considered quite prestigious because Crays were extremely expensive machines, new vendors introduced small supercomputers, known as minisupercomputers during the late 1980s and early 1990s, which out-competed low-end Cray machines in the market
4.
Supercomputer
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A supercomputer is a computer with a high level of computing performance compared to a general-purpose computer. Performance of a supercomputer is measured in floating-point operations per second instead of instructions per second. As of 2015, there are supercomputers which can perform up to quadrillions of FLOPS and it tops the rankings in the TOP500 supercomputer list. Sunway TaihuLights emergence is also notable for its use of indigenous chips, as of June 2016, China, for the first time, had more computers on the TOP500 list than the United States. However, U. S. built computers held ten of the top 20 positions, in November 2016 the U. S. has five of the top 10, throughout their history, they have been essential in the field of cryptanalysis. The use of multi-core processors combined with centralization is an emerging trend, the history of supercomputing goes back to the 1960s, with the Atlas at the University of Manchester and a series of computers at Control Data Corporation, designed by Seymour Cray. These used innovative designs and parallelism to achieve superior computational peak performance, Cray left CDC in 1972 to form his own company, Cray Research. Four years after leaving CDC, Cray delivered the 80 MHz Cray 1 in 1976, the Cray-2 released in 1985 was an 8 processor liquid cooled computer and Fluorinert was pumped through it as it operated. It performed at 1.9 gigaflops and was the second fastest after M-13 supercomputer in Moscow. Fujitsus Numerical Wind Tunnel supercomputer used 166 vector processors to gain the top spot in 1994 with a speed of 1.7 gigaFLOPS per processor. The Hitachi SR2201 obtained a performance of 600 GFLOPS in 1996 by using 2048 processors connected via a fast three-dimensional crossbar network. The Intel Paragon could have 1000 to 4000 Intel i860 processors in various configurations, the Paragon was a MIMD machine which connected processors via a high speed two dimensional mesh, allowing processes to execute on separate nodes, communicating via the Message Passing Interface. Approaches to supercomputer architecture have taken dramatic turns since the earliest systems were introduced in the 1960s, early supercomputer architectures pioneered by Seymour Cray relied on compact innovative designs and local parallelism to achieve superior computational peak performance. However, in time the demand for increased computational power ushered in the age of massively parallel systems, supercomputers of the 21st century can use over 100,000 processors connected by fast connections. The Connection Machine CM-5 supercomputer is a parallel processing computer capable of many billions of arithmetic operations per second. Throughout the decades, the management of heat density has remained a key issue for most centralized supercomputers, the large amount of heat generated by a system may also have other effects, e. g. reducing the lifetime of other system components. There have been diverse approaches to management, from pumping Fluorinert through the system. Systems with a number of processors generally take one of two paths
5.
Computer cluster
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A computer cluster consists of a set of loosely or tightly connected computers that work together so that, in many respects, they can be viewed as a single system. Unlike grid computers, computer clusters have each set to perform the same task. The components of a cluster are usually connected to each other through fast local area networks and they have a wide range of applicability and deployment, ranging from small business clusters with a handful of nodes to some of the fastest supercomputers in the world such as IBMs Sequoia. The desire to get more computing power and better reliability by orchestrating a number of low-cost commercial off-the-shelf computers has given rise to a variety of architectures, the computer clustering approach usually connects a number of readily available computing nodes via a fast local area network. g. Via a single system image concept, Computer clustering relies on a centralized management approach which makes the nodes available as orchestrated shared servers. It is distinct from other such as peer to peer or grid computing which also use many nodes. A computer cluster may be a simple system which just connects two personal computers, or may be a very fast supercomputer. A basic approach to building a cluster is that of a Beowulf cluster which may be built with a few computers to produce a cost-effective alternative to traditional high performance computing. An early project that showed the viability of the concept was the 133-node Stone Soupercomputer, the developers used Linux, the Parallel Virtual Machine toolkit and the Message Passing Interface library to achieve high performance at a relatively low cost. Although a cluster may consist of just a few personal computers connected by a simple network, greg Pfister has stated that clusters were not invented by any specific vendor but by customers who could not fit all their work on one computer, or needed a backup. Pfister estimates the date as some time in the 1960s, the first production system designed as a cluster was the Burroughs B5700 in the mid-1960s. This allowed up to four computers, each with one or two processors, to be tightly coupled to a common disk storage subsystem in order to distribute the workload. Unlike standard multiprocessor systems, each computer could be restarted without disrupting overall operation, the first commercial loosely coupled clustering product was Datapoint Corporations Attached Resource Computer system, developed in 1977, and using ARCnet as the cluster interface. Clustering per se did not really take off until Digital Equipment Corporation released their VAXcluster product in 1984 for the VAX/VMS operating system, the ARC and VAXcluster products not only supported parallel computing, but also shared file systems and peripheral devices. The idea was to provide the advantages of parallel processing, while maintaining data reliability, two other noteworthy early commercial clusters were the Tandem Himalayan and the IBM S/390 Parallel Sysplex. Within the same frame, while computer clusters used parallelism outside the computer on a commodity network. Following the success of the CDC6600 in 1964, the Cray 1 was delivered in 1976, while early supercomputers excluded clusters and relied on shared memory, in time some of the fastest supercomputers relied on cluster architectures. Computer clusters may be configured for different purposes ranging from general purpose business needs such as web-service support, in either case, the cluster may use a high-availability approach
6.
Cray-2
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The Cray-2 is a supercomputer with four vector processors built with emitter-coupled logic and 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, the Cray-2 was replaced as the worlds fastest computer by the ETA-10G in 1990. With the successful launch of his famed Cray-1, Seymour Cray turned to the design of its successor. By 1979 he had become fed up with management interruptions in what was now a large company, and as he had done in the past, decided to resign his management post and move to form a new lab. As with his move to Chippewa Falls, Wisconsin from Control Data HQ in Minneapolis, Minnesota, Cray management understood his needs and supported his move to a new lab in Boulder. Working as an independent consultant at these new Cray Labs, he put together a team and this Lab would later close, and a decade later a new facility in Colorado Springs would open. The classic example of design is the CDC8600, which packed four CDC 7600-like machines based on ECL logic into a 1 x 1 meter cylinder. Unfortunately the density needed to achieve this cycle time led to the machines downfall, one solution to this problem, one that most computer vendors had already moved to, was to use integrated circuits instead of individual components. Each IC included a selection of components from a module pre-wired into a circuit by the construction process. If an IC did not work, another one would be tried, at the time the 8600 was being designed the simple MOSFET-based technology did not offer the speed Cray needed. Relentless improvements changed things by the mid-1970s, however, and the Cray-1 had been able to use newer ICs, in fact, the Cray-1 was actually somewhat faster than the 8600 because it packed considerably more logic into the system due to the ICs small size. Although IC design continued to improve, the size of the ICs was constrained largely by mechanical limits. In order to gain another 10-fold increase in performance over the Cray-1, the goal Cray aimed for, another design problem was the increasing performance gap between the processor and main memory. In the era of the CDC6600 memory ran at the speed as the processor. Cray solved this by adding ten smaller computers to the system, allowing them to deal with the external storage. Adding four processors simply made this problem worse and it was the foreground processors task to run the computer, handling storage and making efficient use of the multiple channels into main memory. It drove the background processors by passing in the instructions they should run via eight 16 word buffers, modern CPUs use a variation of this design as well, although the foreground processor is now referred to as the load/store unit and is not a complete machine unto its own. Main memory banks were arranged in quadrants to be accessed at the same time, the downside to this approach is that the cost of setting up the scatter/gather unit in the foreground processor was fairly high
7.
UNIX System V
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UNIX System V is one of the first commercial versions of the Unix operating system. It was originally developed by AT&T and first released in 1983, four major versions of System V were released, numbered 1,2,3, and 4. It was the source of common commercial Unix features. System V is sometimes abbreviated to SysV, as of 2012, the Unix market is divided between three System V variants, IBMs AIX, Hewlett-Packards HP-UX and Oracles Solaris. System V was the successor to 1982s UNIX System III, while AT&T sold their own hardware that ran System V, most customers instead ran a version from a reseller, based on AT&Ts reference implementation. A standards document called the System V Interface Definition outlined the default features, in the 1980s and early-1990s, System V was considered one of the two major versions of UNIX, the other being the Berkeley Software Distribution. Historically, BSD was also commonly called BSD Unix or Berkeley Unix, the dispute had several levels, some technical and some cultural. The divide was roughly between longhairs and shorthairs, programmers and technical people tended to line up with Berkeley and BSD, more business-oriented types with AT&T and System V. While HP, IBM and others chose System V as the basis for their Unix offerings, other such as Sun Microsystems. Throughout its development, though, System V was infused with features from BSD, since the early 1990s, due to standardization efforts such as POSIX and the commercial success of Linux, the division between System V and BSD has become less important. System V, known inside Bell Labs as Unix 5.0, there was never an external release of Unix 4.0, which would have been System IV. This first release of System V was developed by AT&Ts UNIX Support Group, System V also included features such as the vi editor and curses from 4.1 BSD, developed at the University of California, Berkeley, it also improved performance by adding buffer and inode caches. It also added support for communication using messages, semaphores. SVR1 ran on DEC PDP-11 and VAX minicomputers, System V Release 2 was released in April,1984. It added shell functions and the SVID, new kernel features included record and file locking, demand paging, and copy on write. The concept of the base was formalized, and the DEC VAX-11/780 was chosen for this release. The porting base is the original version of a release. Educational source licenses for SVR2 were offered by AT&T for US$800 for the first CPU, a commercial source license was offered for $43,000, with three months of support, and a $16,000 price per additional CPU
8.
Berkeley Software Distribution
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Berkeley Software Distribution is a Unix operating system derivative developed and distributed by the Computer Systems Research Group of the University of California, Berkeley, from 1977 to 1995. Today the term BSD is often used non-specifically to refer to any of the BSD descendants which together form a branch of the family of Unix-like operating systems, operating systems derived from the original BSD code remain actively developed and widely used. Historically, BSD has been considered a branch of Unix, Berkeley Unix, because it shared the initial codebase, in the 1980s, BSD was widely adopted by vendors of workstation-class systems in the form of proprietary Unix variants such as DEC ULTRIX and Sun Microsystems SunOS. This can be attributed to the ease with which it could be licensed, FreeBSD, OpenBSD, NetBSD, Darwin, and PC-BSD. The earliest distributions of Unix from Bell Labs in the 1970s included the source code to the system, allowing researchers at universities to modify. A larger PDP-11/70 was installed at Berkeley the following year, using money from the Ingres database project, also in 1975, Ken Thompson took a sabbatical from Bell Labs and came to Berkeley as a visiting professor. He helped to install Version 6 Unix and started working on a Pascal implementation for the system, graduate students Chuck Haley and Bill Joy improved Thompsons Pascal and implemented an improved text editor, ex. Other universities became interested in the software at Berkeley, and so in 1977 Joy started compiling the first Berkeley Software Distribution, 1BSD was an add-on to Version 6 Unix rather than a complete operating system in its own right. Some thirty copies were sent out, some 75 copies of 2BSD were sent out by Bill Joy. 2. 9BSD from 1983 included code from 4. 1cBSD, the most recent release,2. 11BSD, was first issued in 1992. As of 2008, maintenance updates from volunteers are still continuing, a VAX computer was installed at Berkeley in 1978, but the port of Unix to the VAX architecture, UNIX/32V, did not take advantage of the VAXs virtual memory capabilities. 3BSD was also alternatively called Virtual VAX/UNIX or VMUNIX, and BSD kernel images were normally called /vmunix until 4. 4BSD, 4BSD offered a number of enhancements over 3BSD, notably job control in the previously released csh, delivermail, reliable signals, and the Curses programming library. In a 1985 review of BSD releases, John Quarterman et al, many installations inside the Bell System ran 4. 1BSD. 4. 1BSD was a response to criticisms of BSDs performance relative to the dominant VAX operating system, the 4. 1BSD kernel was systematically tuned up by Bill Joy until it could perform as well as VMS on several benchmarks. Back at Bell Labs,4. 1cBSD became the basis of the 8th Edition of Research Unix, to guide the design of 4. The committee met from April 1981 to June 1983, apart from the Fast File System, several features from outside contributors were accepted, including disk quotas and job control. Sun Microsystems provided testing on its Motorola 68000 machines prior to release, the official 4. 2BSD release came in August 1983. On a lighter note, it marked the debut of BSDs daemon mascot in a drawing by John Lasseter that appeared on the cover of the printed manuals distributed by USENIX
9.
Cray X-MP
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The Cray X-MP is a supercomputer designed, built and sold by Cray Research. It was announced in 1982 as the cleaned up successor to the 1975 Cray-1, the principal designer was Steve Chen. The X-MPs main improvement over the Cray-1 was that it was a parallel vector processor. It housed two CPUs in a mainframe that was identical in outside appearance to the Cray-1. The X-MP CPU had a faster 9.5 nanosecond clock cycle and 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, each CPU had a theoretical peak performance of 200 MFLOPS, for a peak system performance of 400 MFLOPS. The X-MP initially supported 2 million 64-bit words of memory in 16 banks. Memory bandwidth was significantly improved over the Cray-1—instead of one port for both reads and writes, there were now two read ports, one port, and one dedicated to I/O. The main memory was built from 4 Kbit bipolar SRAM ICs, CMOS memory versions of the Cray-1M were renamed Cray X-MP/1s. This configuration was first used for Cray Researchs UNIX port, in 1984, improved models of the X-MP were announced, consisting of one, two, and four-processor systems with 4 and 8 million word configurations. The top-end system was the X-MP/48, which contained four CPUs with a peak system performance of over 800 MFLOPS and 8 million words of memory. The CPUs in these models introduced vector gather/scatter memory reference instructions to the product line, the amount of main memory supported was increased to a maximum of 16 million words, depending on the model. The main memory was built from bipolar or MOS SRAM ICs, the system initially ran the proprietary Cray Operating System and was object-code compatible with the Cray-1. A UNIX System V derivative initially named CX-OS and finally renamed UniCOS ran through a guest operating system facility, UniCOS became the main OS from 1986 onwards. The DOE ran the Cray Time Sharing System OS instead, see the Software section for the Cray 1 for a more detailed elaboration of software as X-MPs and 1s were mostly compatible. Cray Research announced the X-MP Extended Architecture series in 1986, the EA series CPU had an 8.5 ns clock cycle, and was built from macrocell array and gate array ICs. The EA series extended the width of the A and B registers to 32 bits and performed 32-bit address arithmetic, the largest configuration produced was 64 million words of MOS SRAM in 64 banks. For compatibility with existing software written for the Cray-1 and older X-MP models, each EA series CPUs peak performance was 234 MFLOPS
10.
Unix
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Among these is Apples macOS, which is the Unix version with the largest installed base as of 2014. Many Unix-like operating systems have arisen over the years, of which Linux is the most popular, Unix was originally meant to be a convenient platform for programmers developing software to be run on it and on other systems, rather than for non-programmer users. The system grew larger as the system started spreading in academic circles, as users added their own tools to the system. Unix was designed to be portable, multi-tasking and multi-user in a time-sharing configuration and these concepts are collectively known as the Unix philosophy. By the early 1980s users began seeing Unix as a universal operating system. Under Unix, the system consists of many utilities along with the master control program. To mediate such access, the kernel has special rights, reflected in the division between user space and kernel space, the microkernel concept was introduced in an effort to reverse the trend towards larger kernels and return to a system in which most tasks were completed by smaller utilities. In an era when a standard computer consisted of a disk for storage and a data terminal for input and output. However, modern systems include networking and other new devices, as graphical user interfaces developed, the file model proved inadequate to the task of handling asynchronous events such as those generated by a mouse. In the 1980s, non-blocking I/O and the set of inter-process communication mechanisms were augmented with Unix domain sockets, shared memory, message queues, and semaphores. In microkernel implementations, functions such as network protocols could be moved out of the kernel, Multics introduced many innovations, but had many problems. Frustrated by the size and complexity of Multics but not by the aims and their last researchers to leave Multics, Ken Thompson, Dennis Ritchie, M. D. McIlroy, and J. F. Ossanna, decided to redo the work on a much smaller scale. The name Unics, a pun on Multics, was suggested for the project in 1970. Peter H. Salus credits Peter Neumann with the pun, while Brian Kernighan claims the coining for himself, in 1972, Unix was rewritten in the C programming language. Bell Labs produced several versions of Unix that are referred to as Research Unix. In 1975, the first source license for UNIX was sold to faculty at the University of Illinois Department of Computer Science, UIUC graduate student Greg Chesson was instrumental in negotiating the terms of this license. During the late 1970s and early 1980s, the influence of Unix in academic circles led to adoption of Unix by commercial startups, including Sequent, HP-UX, Solaris, AIX. In the late 1980s, AT&T Unix System Laboratories and Sun Microsystems developed System V Release 4, in the 1990s, Unix-like systems grew in popularity as Linux and BSD distributions were developed through collaboration by a worldwide network of programmers
11.
Fortran
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Fortran is a general-purpose, imperative programming language that is especially suited to numeric computation and scientific computing. It is a language for high-performance computing and is used for programs that benchmark. Fortran encompasses a lineage of versions, each of which evolved to add extensions to the language while usually retaining compatibility with prior versions, the names of earlier versions of the language through FORTRAN77 were conventionally spelled in all-capitals. The capitalization has been dropped in referring to newer versions beginning with Fortran 90, the official language standards now refer to the language as Fortran rather than all-caps FORTRAN. In late 1953, John W. Backus submitted a proposal to his superiors at IBM to develop a practical alternative to assembly language for programming their IBM704 mainframe computer. Backus historic FORTRAN team consisted of programmers Richard Goldberg, Sheldon F. Best, Harlan Herrick, Peter Sheridan, Roy Nutt, Robert Nelson, Irving Ziller, Lois Haibt, and David Sayre. Its concepts included easier entry of equations into a computer, a developed by J. Halcombe Laning and demonstrated in the Laning. A draft specification for The IBM Mathematical Formula Translating System was completed by mid-1954, the first manual for FORTRAN appeared in October 1956, with the first FORTRAN compiler delivered in April 1957. John Backus said during a 1979 interview with Think, the IBM employee magazine, the language was widely adopted by scientists for writing numerically intensive programs, which encouraged compiler writers to produce compilers that could generate faster and more efficient code. The inclusion of a complex data type in the language made Fortran especially suited to technical applications such as electrical engineering. By 1960, versions of FORTRAN were available for the IBM709,650,1620, significantly, the increasing popularity of FORTRAN spurred competing computer manufacturers to provide FORTRAN compilers for their machines, so that by 1963 over 40 FORTRAN compilers existed. For these reasons, FORTRAN is considered to be the first widely used programming language supported across a variety of computer architectures, the arithmetic IF statement was similar to a three-way branch instruction on the IBM704. However, the 704 branch instructions all contained only one destination address, an optimizing compiler like FORTRAN would most likely select the more compact and usually faster Transfers instead of the Compare. Also the Compare considered −0 and +0 to be different values while the Transfer Zero, the FREQUENCY statement in FORTRAN was used originally to give branch probabilities for the three branch cases of the arithmetic IF statement. The Monte Carlo technique is documented in Backus et al, many years later, the FREQUENCY statement had no effect on the code, and was treated as a comment statement, since the compilers no longer did this kind of compile-time simulation. A similar fate has befallen compiler hints in other programming languages. The first FORTRAN compiler reported diagnostic information by halting the program when an error was found and that code could be looked up by the programmer in a error messages table in the operators manual, providing them with a brief description of the problem. Before the development of disk files, text editors and terminals, programs were most often entered on a keyboard onto 80-column punched cards
12.
Pascal (programming language)
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A derivative known as Object Pascal designed for object-oriented programming was developed in 1985. Pascal, named in honor of the French mathematician, philosopher, before his work on Pascal, Wirth had developed Euler and ALGOL W and later went on to develop the Pascal-like languages Modula-2 and Oberon. Initially, Pascal was largely, but not exclusively, intended to teach structured programming. A generation of students used Pascal as a language in undergraduate courses. Variants of Pascal have also frequently used for everything from research projects to PC games. Newer Pascal compilers exist which are widely used, Pascal was the primary high-level language used for development in the Apple Lisa, and in the early years of the Macintosh. Parts of the original Macintosh operating system were hand-translated into Motorola 68000 assembly language from the Pascal sources, apollo Computer used Pascal as the systems programming language for its operating systems beginning in 1980. Object Pascal is still used for developing Windows applications but also has the ability to compile the same code to Mac, iOS. Another cross-platform version called Free Pascal, with the Lazarus IDE, is popular with Linux users since it also offers write once, codeTyphon is a Lazarus distribution with more preinstalled packages and cross compilers. Wirths intention was to create an efficient language based on structured programming, important features included for this were records, enumerations, subranges, dynamically allocated variables with associated pointers, and sets. To make this possible and meaningful, Pascal has a strong typing on all objects, similar mechanisms are standard in many programming languages today. This enables a very simple and coherent syntax where a program is syntactically nearly identical to a single procedure or function. The first Pascal compiler was designed in Zürich for the CDC6000 series mainframe computer family, Niklaus Wirth reports that a first attempt to implement it in Fortran in 1969 was unsuccessful due to Fortrans inadequacy to express complex data structures. The second attempt was implemented in a C-like language and then translated by hand to Pascal itself for boot-strapping, the GNU Pascal compiler is one notable exception, being written in C. The first successful port of the CDC Pascal compiler to another mainframe was completed by Welsh, the target was the ICL1900 series. This compiler, in turn, was the parent of the Pascal compiler for the Information Computer Systems Multum minicomputer and it is thought that Multum Pascal, which was completed in the summer of 1973, may have been the first 16-bit implementation. A completely new compiler was completed by Welsh et al. at QUB in 1977 and it offered a source-language diagnostic feature that was implemented by Findlay and Watt at Glasgow University. This implementation was ported in 1980 to the ICL2900 series by a team based at Southampton University, the first Pascal compiler written in North America was constructed at the University of Illinois under Donald B
13.
Bell Labs
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Nokia Bell Labs is an American research and scientific development company, owned by Finnish company Nokia. Its headquarters are located in Murray Hill, New Jersey, in addition to laboratories around the rest of the United States. The historic laboratory originated in the late 19th century as the Volta Laboratory, Bell Labs was also at one time a division of the American Telephone & Telegraph Company, half-owned through its Western Electric manufacturing subsidiary. Eight Nobel Prizes have been awarded for work completed at Bell Laboratories, in 1880, the French government awarded Alexander Graham Bell the Volta Prize of 50,000 francs, approximately US$10,000 at that time for the invention of the telephone. Bell used the award to fund the Volta Laboratory in Washington, D. C. in collaboration with Sumner Tainter, the laboratory is also variously known as the Volta Bureau, the Bell Carriage House, the Bell Laboratory and the Volta Laboratory. The laboratory focused on the analysis, recording, and transmission of sound, Bell used his considerable profits from the laboratory for further research and education to permit the diffusion of knowledge relating to the deaf. This resulted in the founding of the Volta Bureau c,1887, located at Bells fathers house at 1527 35th Street in Washington, D. C. where its carriage house became their headquarters in 1889. In 1893, Bell constructed a new building, close by at 1537 35th St. specifically to house the lab, the building was declared a National Historic Landmark in 1972. In 1884, the American Bell Telephone Company created the Mechanical Department from the Electrical, the first president of research was Frank B. Jewett, who stayed there until 1940, ownership of Bell Laboratories was evenly split between AT&T and the Western Electric Company. Its principal work was to plan, design, and support the equipment that Western Electric built for Bell System operating companies and this included everything from telephones, telephone exchange switches, and transmission equipment. Bell Labs also carried out consulting work for the Bell Telephone Company, a few workers were assigned to basic research, and this attracted much attention, especially since they produced several Nobel Prize winners. Until the 1940s, the principal locations were in and around the Bell Labs Building in New York City. Of these, Murray Hill and Crawford Hill remain in existence, the largest grouping of people in the company was in Illinois, at Naperville-Lisle, in the Chicago area, which had the largest concentration of employees prior to 2001. Since 2001, many of the locations have been scaled down or closed. The Holmdel site, a 1.9 million square foot structure set on 473 acres, was closed in 2007, the mirrored-glass building was designed by Eero Saarinen. In August 2013, Somerset Development bought the building, intending to redevelop it into a commercial and residential project. The prospects of success are clouded by the difficulty of readapting Saarinens design and by the current glut of aging, eight Nobel Prizes have been awarded for work completed at Bell Laboratories
14.
Dennis Ritchie
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Dennis MacAlistair Ritchie was an American computer scientist. He created the C programming language and, with long-time colleague Ken Thompson, Ritchie and Thompson received the Turing Award from the ACM in 1983, the Hamming Medal from the IEEE in 1990 and the National Medal of Technology from President Bill Clinton in 1999. Ritchie was the head of Lucent Technologies System Software Research Department when he retired in 2007 and he was the R in K&R C, and commonly known by his username dmr. Dennis Ritchie was born in Bronxville, New York and his father was Alistair E. Ritchie, a longtime Bell Labs scientist and co-author of The Design of Switching Circuits on switching circuit theory. As a child, Dennis moved with his family to Summit, New Jersey and he graduated from Harvard University with degrees in physics and applied mathematics. However, Ritchie never officially received his PhD degree, during the 1960s, Ritchie and Ken Thompson worked on the Multics operating system at Bell Labs. However, Bell Labs pulled out of the project in 1969, Thompson then found an old PDP-7 machine and developed his own application programs and operating system from scratch, aided by Ritchie and others. In 1970, Brian Kernighan suggested the name Unix, a pun on the name Multics, to supplement assembly language with a system-level programming language, Thompson created B. Later, B was replaced by C, created by Ritchie, during the 1970s, Ritchie collaborated with James Reeds and Robert Morris on a ciphertext-only attack on the M-209 US cipher machine that could solve messages of at least 2000–2500 letters. Ritchie relates that, after discussions with the NSA, the decided not to publish it. Ritchie was also involved with the development of the Plan 9 and Inferno operating systems, and they were so influential on Research Unix that Doug McIlroy later wrote, The names of Ritchie and Thompson may safely be assumed to be attached to almost everything not otherwise attributed. Ritchie liked to emphasize that he was just one member of a group and he suggested that many of the improvements he introduced simply looked like a good thing to do, and that anyone else in the same place at the same time might have done the same thing. But Bjarne Stroustrup who designed C++ said If Dennis had decided to spend that decade on esoteric math, nowadays, the C language is widely used today in application, operating system, and embedded system development, and its influence is seen in most modern programming languages. Unix has also been influential, establishing computing concepts and principles that have been widely adopted, in the same interview, he stated that he viewed both Unix and Linux as the continuation of ideas that were started by Ken and me and many others, many years ago. In 1983, Ritchie and Thompson received the Turing Award for their development of operating systems theory. Ritchies Turing Award lecture was titled Reflections on Software Research, in 1997, both Ritchie and Thompson were made Fellows of the Computer History Museum, for co-creation of the UNIX operating system, and for development of the C programming language. In 2011, Ritchie, along with Thompson, was awarded the Japan Prize for Information, Ritchie was found dead on October 12,2011, at the age of 70 at his home in Berkeley Heights, New Jersey, where he lived alone. First news of his death came from his colleague, Rob Pike
15.
Research Unix
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The term Research Unix first appeared in the Bell System Technical Journal to distinguish it from other versions internal to Bell Labs whose code-base had diverged from the primary CSRC version. However, that term was little-used until Version 8 Unix, but has been applied to earlier versions as well. Prior to V8, the system was most commonly called simply UNIX or the UNIX Time-Sharing System. AT&T licensed Version 5 to educational institutions, and Version 6 also to commercial sites, schools paid $200 and others $20,000, discouraging most commercial use, but Version 6 was the most widely used version into the 1980s. So, the first Research Unix would be the First Edition, another common way of referring to them is Version x Unix, where x is the manual edition. All modern editions of Unix—excepting Unix-like implementations such as Coherent, Minix, starting with the 8th Edition, versions of Research Unix had a close relationship to BSD. This began by using 4. 1cBSD as the basis for the 8th Edition. 1c and this continued with 9th and 10th. The ordinary user command-set was, I guess, a bit more BSD-flavored than SysVish, Version 3, Version 4 and Version 5 should not be confused with the UNIX3.0, UNIX4.0 and UNIX5.0 releases by the AT&T UNIX Support Group. After Version 10, Unix development at Bell Labs was stopped in favor of a system, Plan 9 from Bell Labs. In 2002, Caldera International released V7 Unix as FOSS under a permissive BSD-like software license, in 2017, Unix Heritage Society and Alcatel-Lucent USA Inc. List of new features in Research Unix 9th Edition
16.
STREAMS
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In computer networking, STREAMS is the native framework in Unix System V for implementing character device drivers, network protocols, and inter-process communication. In this framework, a stream is a chain of coroutines that pass messages between a program and a device driver, STREAMS originated in Version 8 Research Unix, as Streams. STREAMSs design is an architecture for implementing full-duplex I/O between kernel and device drivers. Its most frequent uses have been in developing terminal I/O and networking subsystems, in System V Release 4, the entire terminal interface was reimplemented using STREAMS. An important concept in STREAMS is the ability to push drivers – custom code modules which can modify the functionality of an interface or other device – together to form a stack. Several of these drivers can be chained together in order and it was first released with the Network Support Utilities package of UNIX System V Release 3. This port added the putmsg, getmsg, and poll system calls, which are equivalent in purpose to the send, recv. The putmsg and getmsg system calls were originally called send and recv, in System V Release 4, STREAMS was extended and used for the terminal I/O framework and pipes, providing useful new functionality like bidirectional pipes and file descriptor passing. A port for Unicos was also produced, eric S. Raymond quotes Ritchie as saying about the complexity of System V STREAMS when compared to his V8 Streams that Streams means something different when shouted. Concurrent with the System V Release 3 port, AT&T developed protocol-independent STREAMS message passing guidelines for the link, network, in conjunction with the transport message passing model, the Transport Layer Interface was defined to provide a transport protocol-independent API for application development. Also, a library supporting the session, presentation and application layers was defined, POSIX. 1-2008 with TC1 has designated STREAMS as marked obsolescent meaning that said functionality may be removed in a future version of the specification. However, the definition of obsolescent used also says that strictly conforming POSIX applications shall not use obsolescent features. Streams replaced this with a set of processing modules organized in a chain that allowed bidirectional communication with between neighboring modules. Programs could push a new module onto one end of the chain to change the behavior of a terminal or other character device, Ritchie gives the example chain of a terminal modules chained with a Datakit network module to achieve remote login over a network. Aside from characters going from program to device and vice versa, Streams could carry messages such as hangup. Streams could also be used for communication, by connecting two processes to pseudoterminals. This possibility was in the mpx window system for the Blit graphics terminal, control signals designated the users wish to switch between windows or close them. The actual Streams modules lives in space on Unix, and are installed and removed by the ioctl system call
17.
Cray-1
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The Cray-1 was a supercomputer designed, manufactured and marketed by Cray Research. The first Cray-1 system was installed at Los Alamos National Laboratory in 1976 and it went on to one of the best known. The Cray-1s architect was Seymour Cray, the engineer was Cray Research co-founder Lester Davis. From 1968 to 1972 Seymour Cray of Control Data Corporation worked on the CDC8600, the 8600 was essentially made up of four 7600s in a box with an additional special mode that allowed them to operate lock-step in a SIMD fashion. Jim Thornton, formerly Crays engineering partner on earlier designs, had started a more radical project known as the CDC STAR-100, unlike the 8600s brute-force approach to performance, the STAR took an entirely different route. In fact the main processor of the STAR had less performance than the 7600, by 1972, the 8600 had reached a dead end, the machine was so incredibly complex that it was impossible to get one working properly. Even a single faulty component would render the machine non-operational, Cray went to William Norris, Control Datas CEO, saying that a redesign from scratch was needed. At the time the company was in financial trouble, and with the STAR in the pipeline as well. As a result, Cray left CDC and started Cray Research very close to the CDC lab, in the back yard of the land he purchased in Chippewa Falls, Cray and a group of former CDC employees started looking for ideas. For four years Cray Research designed its first computer, in 1975 the 80 MHz Cray-1 was announced. The National Center for Atmospheric Research was the first official customer of Cray Research in 1977, the NCAR machine was decommissioned in 1989. The company expected to sell perhaps a dozen of the machines, and set the selling price accordingly, the machine made Seymour Cray a celebrity and his company a success, lasting until the supercomputer crash in the early 1990s. Based on a recommendation by William Perrys study, the NSA purchased a Cray-1 for theoretical research in cryptanalysis. According to Budiansky, Though standard histories of Cray Research would persist for decades in stating that the companys first customer was Los Alamos National Laboratory, the 160 MFLOPS Cray-1 was succeeded in 1982 by the 800 MFLOPS Cray X-MP, the first Cray multi-processing computer. A more conservatively designed evolutionary successor of the Cray-1 and X-MP models was made by the name Cray Y-MP. As a comparison standpoint, the processor in a typical 2013 smartphone performs at roughly 1 GFLOPS, typical scientific workloads consist of reading in large data sets, transforming them in some way and then writing them back out again. Normally the transformations being applied are identical across all of the points in the set. For instance, the program might add 5 to every number in a set of a million numbers, in traditional computers the program would loop over all million numbers, adding five, thereby executing a million instructions saying a = add b, c
18.
Cray Y-MP
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The Cray Y-MP was a supercomputer sold by Cray Research from 1988, and the successor to the companys X-MP. The Y-MP retained software compatibility with the X-MP, but extended the registers from 24 to 32 bits. High-density VLSI ECL technology was used and a new 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. Peak performance was thus 333 megaflops per processor, main memory comprised 128,256 or 512 MB of SRAM. The original Y-MP was housed in a chassis to the horseshoe-shaped X-MP. The system could be configured with one or two Model D IOSs and an optional Solid State Disk of 256 MB to 4GB capacity, the Y-MP had a measured GFLOPS of 2.144 and a peak GFLOPS of 2.667 in both 1988 and 1989. The Model D Y-MP was superseded in 1990 by the Y-MP Model E, the Y-shaped chassis was dropped in favor of one or two rectangular cabinets, depending on configuration. Maximum RAM was increased to 2 GB and up to eight IOSs were possible, Model E variants included the Y-MP 2E, Y-MP 4E, Y-MP 8E and Y-MP 8I, the latter being a single-cabinet version of the two-cabinet 8E. The 2E and 4E were later available with optional secondary air cooling, the Y-MP M90 was a large-memory variant of the Y-MP Model E introduced in 1992. This replaced the SRAM of the Y-MP with up to 32 GB of slower, the Y-MP M90 was also available in variants with up to two, four or eight processors. Later, the name was abbreviated to the Cray M90 series. The Y-MP C90 series is described separately, in 1992, Cray launched the cheaper Y-MP EL model. This was a reimplementation of the Y-MP architecture in CMOS technology, the EL was an air-cooled system with a completely different VMEbus-based IOS. EL configurations with up to four processors and 32 MB to 1 GB of DRAM were available, the Y-MP EL was later developed into the Cray EL90 series. The Y-MP EL came in a much smaller than the traditional room-filling Cray 2010×1270×810 mm and 635 kg in weight—and could be powered from regular mains power. In the 1992 film Sneakers, whose story is centered around extremely high level cryptography, in an episode of the television dramedy Northern Exposure titled Nothings Perfect, a character expresses her excitement at having finally gained access to a CRAY Y-MP3 supercomputer. Past, Present, Parallel, A Survey of Available Parallel Computing Systems, fred Gannetts Cray FAQ, Part 1 Working online Cray Y-MP EL in Cray-Cyber museum
19.
Cray C90
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The Cray C90 series was a vector processor supercomputer launched by Cray Research in 1991. The C90 was a development of the Cray Y-MP architecture, compared to the Y-MP, the C90 processor had a dual vector pipeline and a faster 4.1 ns clock cycle, which together gave three times the performance of the Y-MP processor. The maximum number of processors in a system was doubled from eight to 16. The C90 series used the same Model E IOS and UNICOS operating system as the earlier Y-MP Model E, the C90 series included the C94, C98 and C916 models and the C92A and C94A. Maximum SRAM memory was between 1 and 8 GB, depending on model, the D92, D92A, D94 and D98 variants were equipped with slower, but higher-density DRAM memory, allowing increased maximum memory sizes of up to 16 GB, depending on the model. The successor system was the Cray T90, Cray Research and Cray computers FAQ Part 5
20.
Mach kernel
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Mach is a kernel developed at Carnegie Mellon University to support operating system research, primarily distributed and parallel computing. Mach is often mentioned as one of the earliest examples of a microkernel, however, not all versions of Mach are microkernels. Machs derivatives are the basis of the operating system kernels in GNU Hurd. The project at Carnegie Mellon ran from 1985 to 1994, ending with Mach 3.0, Mach was developed as a replacement for the kernel in the BSD version of Unix, so no new operating system would have to be designed around it. Experimental research on Mach appears to have ended, although Mach and these include NeXTSTEP and OpenStep, upon which macOS is based—all using the XNU operating system kernel which incorporates an earlier, non-microkernel, Mach as a major component. The Mach virtual memory management system was adopted in 4. 4BSD by the BSD developers at CSRG. Mach is the successor to Carnegie Mellons Accent kernel. The lead developer on the Mach project, Richard Rashid, has been working at Microsoft since 1991 in various top-level positions revolving around the Microsoft Research division. Another of the original Mach developers, Avie Tevanian, was head of software at NeXT. Rashid liked Giuses spelling Mach so much that it prevailed, a key concept in the original Unix operating system was the idea of a pipe. A pipe was an abstraction that allowed data to be moved from program to program using the command line, using pipes, users could link together multiple programs to complete tasks, feeding data through several small programs in turn. Pipes were built on the underlying input/output system and this system was, in turn, based on a model where drivers were expected to periodically block while they waited for tasks to complete. For instance, a driver might send a line of text to a line printer. In this case, the driver would indicate that it was blocked, in the pipes system the limited resource was memory, and when one program filled the memory assigned to the pipe, it would naturally block. Normally this would cause the program to run, emptying the pipe out again. However, the implementation of pipes as memory buffers meant data was being copied from program to program and this made the pipe concept unsuitable for tasks where quick turnaround or low latency was needed, as is the case in most device drivers. The operating system kernel and most core functionality was instead written as a large program. As the operating system added new functionality, the size and complexity of the kernel grew, Unix pipes offered a conceptual system that could be used to build arbitrarily complex solutions out of small interacting programs
21.
Microkernel
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In computer science, a microkernel is the near-minimum amount of software that can provide the mechanisms needed to implement an operating system. These mechanisms include low-level address space management, thread management, If the hardware provides multiple rings or CPU modes, the microkernel may be the only software executing at the most privileged level, which is generally referred to as supervisor or kernel mode. Traditional operating system functions, such as drivers, protocol stacks. In terms of the code size, as a general rule microkernels tend to be smaller than monolithic kernels. The MINIX3 microkernel, for example, has approximately 12,000 lines of code, in 1967, Regnecentralen was installing a RC4000 prototype in a Polish fertilizer plant in Puławy. The computer used a small operating system tailored for the needs of the plant. Brinch Hansen and his team became concerned with the lack of generality and reusability of the RC4000 system and they feared that each installation would require a different operating system so they started to investigate novel and more general ways of creating software for the RC4000. In 1969, their effort resulted in the completion of the RC4000 Multiprogramming System and its nucleus provided inter-process communication based on message-passing for up to 23 unprivileged processes, out of which 8 at a time were protected from one another. Besides these elementary mechanisms, it had no strategy for program execution. This strategy was to be implemented by a hierarchy of running programs in which parent processes had complete control over child processes, microkernels were first developed in the 1980s as a response to changes in the computer world, and to several challenges adapting existing mono-kernels to these new systems. New device drivers, protocol stacks, file systems and other systems were being developed all the time. This code was located in the monolithic kernel, and thus required considerable work. This would not only allow these services to be easily worked on. Moreover, it would allow entirely new operating systems to be built up on a common core, microkernels were a very hot topic in the 1980s when the first usable local area networks were being introduced. The same mechanisms that allowed the kernel to be distributed into user space also allowed the system to be distributed across network links. The first microkernels, notably Mach, proved to have disappointing performance, however, during this time the speed of computers grew greatly in relation to networking systems, and the disadvantages in performance came to overwhelm the advantages in development terms. As of 2012, the Mach-based GNU Hurd is also functional and included in testing versions of Arch Linux, although major work on microkernels had largely ended, experimenters continued development. Microkernels are closely related to exokernels, early operating system kernels were rather small, partly because computer memory was limited
22.
Cray T3D
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The T3D was Cray Researchs first attempt at a massively parallel supercomputer architecture. Launched in 1993, it also marked Crays first use of another companys microprocessor, the T3D consisted of between 32 and 2048 Processing Elements, each comprising a 150 MHz DEC Alpha 21064 microprocessor and either 16 or 64 MB of DRAM. PEs were grouped in pairs, or nodes, which incorporated a 6-way processor interconnect switch and these switches had a peak bandwidth of 300 MB/second in each direction and were connected to form a three-dimensional torus network topology. The T3D was designed to be hosted by a Cray Y-MP Model E, M90 or C90-series front-end system and rely on it and its UNICOS operating system for all I/O, the T3D PEs ran a simple microkernel called UNICOS MAX. Several different configurations of T3D were available, the SC models shared a cabinet with a host Y-MP system and were available with either 128 or 256 PEs. The MC models were housed in one or more liquid-cooled cabinet separately from the host, there was also a liquid-cooled MCN model which had an alternative interconnect wiremat allowing non-power-of-2 numbers of PEs. The Cray T3D MC cabinet had an Apple Macintosh PowerBook laptop built into its front and its only purpose was to display animated Cray Research and T3D logos on its color LCD screen. The first T3D delivered was a prototype installed at the Pittsburgh Supercomputing Center in early September 1993, the supercomputer was formally introduced on 27 September 1993. The T3D was superseded in 1995 by the faster and more sophisticated Cray T3E, CRAY T3D System Architecture Overview Manual
23.
Distributed operating system
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A distributed operating system is a software over a collection of independent, networked, communicating, and physically separate computational nodes. Each individual node holds a specific subset of the global aggregate operating system. Each subset is a composite of two distinct service provisioners, the first is a ubiquitous minimal kernel, or microkernel, that directly controls that node’s hardware. Second is a collection of system management components that coordinate the nodes individual. These components abstract microkernel functions and support user applications, the microkernel and the management components collection work together. They support the goal of integrating multiple resources and processing functionality into an efficient. To a user, a distributed OS works in a similar to a single-node. That is, although it consists of nodes, it appears to users. Separating minimal system-level functionality from additional user-level modular services provides a “separation of mechanism and policy. ”Mechanism and policy can be interpreted as what something is done versus how something is done. This separation increases flexibility and scalability, at each locale, the kernel provides a minimally complete set of node-level utilities necessary for operating a node’s underlying hardware and resources. These mechanisms include allocation, management, and disposition of a node’s resources, processes, communication, within the kernel, the communications sub-system is of foremost importance for a distributed OS. In a distributed OS, the kernel often supports a set of functions, including low-level address space management, thread management. A kernel of this design is referred to as a microkernel and its modular nature enhances reliability and security, essential features for a distributed OS. It is common for a kernel to be replicated over all nodes in a system. The combination of design and ubiquitous node coverage enhances the global systems extensibility. System management components are software processes that define the nodes policies and these components are the part of the OS outside the kernel. These components provide higher-level communication, process and resource management, reliability, performance, the components match the functions of a single-entity system, adding the transparency required in a distributed environment. The distributed nature of the OS requires additional services to support a nodes responsibilities to the global system, in addition, the system management components accept the defensive responsibilities of reliability, availability, and persistence
24.
Cray T3E
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The Cray T3E was Cray Researchs second-generation massively parallel supercomputer architecture, launched in late November 1995. The first T3E was installed at the Pittsburgh Supercomputing Center in 1996, like the previous Cray T3D, it was a fully distributed memory machine using a 3D torus topology interconnection network. The T3E initially used the DEC Alpha 21164 microprocessor and was designed to scale from 8 to 2,176 Processing Elements, each PE had between 64 MB and 2 GB of DRAM and a 6-way interconnect router with a payload bandwidth of 480 MB/s in each direction. The original T3E had a 300 MHz processor clock, later variants, using the faster 21164A processor, comprised the T3E-900, T3E-1200, T3E-1200E and T3E-1350. The T3E was available in both air-cooled and liquid-cooled configurations, AC systems were available with 16 to 128 user PEs, LC systems with 64 to 2048 user PEs. A 1480-processor T3E-1200 was the first supercomputer to achieve a performance of more than 1 teraflops running a computational science application, after Cray Research was acquired by Silicon Graphics in February 1996, development of new Alpha-based systems was stopped. However, the T3E continued in production after SGI sold the Cray business the same year, history of supercomputing Top500 description of T3E Inside Cray T3E-900 Serial Number 6702, Performance Analysis of the CRAY T3E-1200E, Edward Anderson, Lockheed Martin Services Inc
25.
IRIX
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IRIX is a discontinued operating system developed by Silicon Graphics to run natively on their MIPS workstations and servers. It is based on UNIX System V with BSD extensions, IRIX was the first operating system to include the XFS file system. The last major version of IRIX was IRIX6.5 which was released in May 1998, new minor versions of IRIX6.5 were released every quarter until 2005, since then there have been four further minor releases. The IRIX name was first used around the time of release 3.0 of the system for SGIs IRIS 4D series of workstations and servers. Previous releases were identified only by the release number prefixed by 4D1-, the 4D1- prefix continued to be used in official documentation to prefix IRIX release numbers. IRIX3. x was based on UNIX System V Release 3 with 4. 3BSD enhancements, SGIs own Extent File System replaced the System V filesystem. IRIX4.0, released in 1991, replaced 4Sight with the X Window System, IRIX5.0, released in 1993, incorporated certain features of UNIX System V Release 4, including ELF executables. IRIX5.3 introduced the XFS journaling file system, in 1994, IRIX6.0 added support for the 64-bit MIPS R8000 processor, but was otherwise similar to IRIX5.2. Later 6. x releases supported other members of the MIPS processor family in 64-bit mode, IRIX6.3 was released for the SGI O2 workstation only. IRIX6.4 improved multiprocessor scalability for the Octane, Origin 2000, the Origin 2000 and Onyx2 IRIX6.4 was marketed as Cellular IRIX, although it only incorporated some features from the original Cellular IRIX distributed operating system project. IRIX development stabilized with IRIX6.5, released in 1998, the last version of IRIX was 6.5.30, released in August 2006. A2001 Computerworld review found IRIX in a critical state, SGI had been moving its efforts to Linux and Windows, but MIPS/IRIX customers had forced it to continue to support that platform through 2006. On September 6 of that year, an SGI press release heralded the end of the MIPS/IRIX product line, production ended on December 29,2006, with last deliveries in March 2007, except by special arrangement. Support for these products ended in December 2013 and they receive no further updates. IRIX6 was compliant with UNIX System V Release 4, UNIX95, IRIX had strong support for real-time disk and graphics I/O. IRIX was one of the first Unix versions to feature a graphical interface for the main desktop environment. IRIX was widely used in the animation industry and for scientific visualization due to its once-large application base. IRIX was a leader in Symmetric Multi-Processing, scalable from 1 to greater than 1024 processors with a system image
26.
Cray X1
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The Cray X1 is a non-uniform memory access, vector processor supercomputer manufactured and sold by Cray Inc. since 2003. The X1 is often described as the unification of the Cray T90, Cray SV1, the X1 uses a 1.2 ns clock cycle, and 8-wide vector pipes in MSP mode, offering a peak speed of 12.8 gigaflops per processor. Air-cooled models are available with up to 64 processors, liquid-cooled systems scale to a theoretical maximum of 4096 processors, comprising 1024 shared-memory nodes connected in a two-dimensional torus network, in 32 frames. Such a system would supply a peak speed of 50 teraflops, the largest unclassified X1 system was the 512 processor system at Oak Ridge National Laboratory, though this has since been upgraded to an X1E system. The X1 can be programmed either with widely used message passing software like MPI and PVM, the X1 runs an operating system called UNICOS/mp which shares more with the SGI IRIX operating system than it does with the UNICOS found on prior generation Cray machines. In 2005, Cray released the X1E upgrade, which uses dual-core processors, the processors are also upgraded to 1150 MHz. This upgrade almost triples the peak performance per board, but reduces the per-processor memory, X1 and X1E boards can be combined within the same system. The X1 is notable for its development being funded by United States Governments National Security Agency. The X1 was not a successful product and it seems doubtful that it or its successors would have been produced without this support. ORNL X1 evaluation Cray Legacy Products Cray X1E at top500. org
27.
SUSE Linux
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SUSE Linux is a computer operating system. It is built on top of the open source Linux kernel and is distributed with system, SUSE Linux is of German origin, basically an acronym of “Software und System-Entwicklung”, and was mainly developed in Europe. The first version appeared in early 1994, making SUSE one of the oldest existing commercial distributions and it is known for its YaST configuration tool. Novell bought the SUSE brands and trademarks in 2003, Novell employed more than 500 developers working on SUSE in 2004. On 27 April 2011, Novell were acquired by The Attachmate Group, later, in October 2014, the entire Attachmate Group, including SUSE, was acquired by the British firm Micro Focus International. SUSE continues to operate as an independent business unit, gesellschaft für Software und System Entwicklung mbH was founded on 2 September 1992 in Nuremberg, Germany, by Roland Dyroff, Thomas Fehr, Burchard Steinbild, and Hubert Mantel. Three of the founders were still students at a university. The original idea was that the company would develop software and function as an advisory UNIX group, according to Mantel, the group decided to distribute Linux, offering support. Their name at founding was S. u. S. E and it was chosen as a German acronym for Software und System-Entwicklung, meaning Software and systems development. The full name has never used, however, and the company was known as S. u. S. E. The official logo and current mascot of the distribution is a veiled chameleon officially named, Geeko, as with the companys name, the Geeko logo design has evolved over time to reflect the name changes. The company started as a provider, which among other things regularly released software packages that included Softlanding Linux System. Also, they printed UNIX/Linux manuals and they offered technical assistance and this was distributed to people who wanted to get Linux via floppy disks. In 1993, Patrick Volkerding cleaned up the SLS Linux distribution, in 1994, in support with Patrick Volkerding, Slackware scripts were translated into German, which was marked as the first release of S. u. S. E. It was available first on floppies, and then on CDs, for building its very own distribution of Linux, S. u. S. E used the jurix distribution as starting point. This was created by Florian La Roche, who joined the S. u. S. E team and he began to develop YaST, the installer and configuration tool that would become the central point of the distribution. In 1996, the first distribution under the name S. u. S. E Linux was published as S. u. S. E Linux 4.2. The version number has caused much discussion, it should have been just a version 1.1, yaSTs first version number,0.42, was a similar reference
28.
Cray XT3
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The Cray XT3 is a distributed memory massively parallel MIMD supercomputer designed by Cray Inc. with Sandia National Laboratories under the codename Red Storm. Cray turned the design into a product in 2004. The XT3 derives much of its architecture from the previous Cray T3E system, the PowerPC440 based SeaStar device provides a 6.4 gigabyte per second connection to the processor across HyperTransport, as well as six 8-gigabyte per second links to neighboring PEs. The PEs are arranged in a 3-dimensional torus topology, with 96 PEs in each cabinet, the XT3 runs an operating system called UNICOS/lc that partitions the machine into three sections, the largest comprising the Compute nodes, and two smaller sections for Service nodes and IO nodes. Service and IO PEs run the full version of SuSE Linux and are used for interactive logins, systems management, application compiling, after upgrades in 2008 to install some XT4 nodes with quad-core Opterons, Red Storm achieved 248 teraflops to place at #9 on the November 2008 Top500. The architecture was superseded in 2006 by the Cray XT4, XT3 at top500. org Fireworks with new products at Cray - the XT3, Primeur, November 2004 Cray XT3 Datasheet
29.
Cray XT4
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The Cray XT4 is an updated version of the Cray XT3 supercomputer. It was released on November 18,2006 and it includes an updated version of the SeaStar interconnect router called SeaStar2, processor sockets for Socket AM2 Opteron processors, and 240-pin unbuffered DDR2 memory. The XT4 also includes support for FPGA coprocessors that plug into riser cards in the Service, the interconnect, cabinet, system software and programming environment remain unchanged from the Cray XT3. It was superseded in 2007 by the Cray XT5, news release regarding Hood Cray Introduces XMT and XT4 Supercomputers on HPCwire Cray XT4 at top500. org
30.
Cray XT5
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The Cray XT5 is an updated version of the Cray XT4 supercomputer, launched on November 6,2007. The XT5 uses a 3-dimensional torus network topology, the XT5 family run the Cray Linux Environment, formerly known as UNICOS/lc. This incorporates SUSE Linux Enterprise Server and Crays Compute Node Linux, the XT5m variant is a mid-ranged supercomputer with most of the features of the XT5, but having a 2-dimensional torus network topology and scalable to 6 cabinets. In the fall of 2008, Cray delivered a 1.3 petaflops XT5 system to National Center for Computational Sciences at Oak Ridge National Laboratories. Jaguar underwent an upgrade to 224,256 cores in 2009, after which its performance jumped to 1.75 petaflops, taking it to the number one position in the 34th edition of the TOP500 list in fall 2009. It remained number one in the June 2010 edition, but in October 2010 was surpassed by the Chinese Tianhe-1A, another XT5 system, Kraken, with 112,896 cores and 1.17 petaflops, as of June 2012 was at position number 21 in the TOP500 list. Cray Introduces Next-Generation Supercomputers Cray Linux Environment
31.
Linux kernel
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The Linux kernel is a monolithic Unix-like computer operating system kernel. The Android operating system for computers, smartphones and smartwatches is also based atop the Linux kernel. While the adoption on desktop computers is low, Linux-based operating systems dominate nearly every segment of computing. As of November 2016, all but two of the worlds 500 most powerful supercomputers run Linux, Linux rapidly attracted developers and users who adopted it as the kernel for other free software projects, notably the GNU Operating System. The Linux kernel has received contributions from nearly 12,000 programmers from more than 1,200 companies, the Linux kernel API, the application programming interface through which user programs interact with the kernel, is meant to be very stable and to not break userspace programs. As part of the functionality, device drivers control the hardware. However, the interface between the kernel and loadable kernel modules, unlike in many other kernels and operating systems, is not meant to be stable by design. The Linux kernel, developed by contributors worldwide, is a prominent example of free, day-to-day development discussions take place on the Linux kernel mailing list. The Linux kernel is released under the GNU General Public License version 2, in April 1991, Linus Torvalds, at the time a 21-year-old computer science student at the University of Helsinki, Finland, started working on some simple ideas for an operating system. He started with a task switcher in Intel 80386 assembly language, on 25 August 1991, Torvalds posted the following to comp. os. minix, a newsgroup on Usenet, Im doing a operating system for 386 AT clones. This has been brewing since April, and is starting to get ready, id like any feedback on things people like/dislike in minix, as my OS resembles it somewhat. Ive currently ported bash and gcc, and things seem to work and this implies that Ill get something practical within a few months Yes - its free of any minix code, and it has a multi-threaded fs. It is NOT portable, and it never will support anything other than AT-harddisks, as thats all I have. Its mostly in C, but most people wouldnt call what I write C and it uses every conceivable feature of the 386 I could find, as it was also a project to teach me about the 386. As already mentioned, it uses a MMU, for both paging and segmentation and its the segmentation that makes it REALLY386 dependent. Some of my C-files are almost as much assembler as C, unlike minix, I also happen to LIKE interrupts, so interrupts are handled without trying to hide the reason behind them. After that, many people contributed code to the project, early on, the MINIX community contributed code and ideas to the Linux kernel. At the time, the GNU Project had created many of the components required for an operating system
32.
SUSE Linux Enterprise
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SUSE Linux is a computer operating system. It is built on top of the open source Linux kernel and is distributed with system, SUSE Linux is of German origin, basically an acronym of “Software und System-Entwicklung”, and was mainly developed in Europe. The first version appeared in early 1994, making SUSE one of the oldest existing commercial distributions and it is known for its YaST configuration tool. Novell bought the SUSE brands and trademarks in 2003, Novell employed more than 500 developers working on SUSE in 2004. On 27 April 2011, Novell were acquired by The Attachmate Group, later, in October 2014, the entire Attachmate Group, including SUSE, was acquired by the British firm Micro Focus International. SUSE continues to operate as an independent business unit, gesellschaft für Software und System Entwicklung mbH was founded on 2 September 1992 in Nuremberg, Germany, by Roland Dyroff, Thomas Fehr, Burchard Steinbild, and Hubert Mantel. Three of the founders were still students at a university. The original idea was that the company would develop software and function as an advisory UNIX group, according to Mantel, the group decided to distribute Linux, offering support. Their name at founding was S. u. S. E and it was chosen as a German acronym for Software und System-Entwicklung, meaning Software and systems development. The full name has never used, however, and the company was known as S. u. S. E. The official logo and current mascot of the distribution is a veiled chameleon officially named, Geeko, as with the companys name, the Geeko logo design has evolved over time to reflect the name changes. The company started as a provider, which among other things regularly released software packages that included Softlanding Linux System. Also, they printed UNIX/Linux manuals and they offered technical assistance and this was distributed to people who wanted to get Linux via floppy disks. In 1993, Patrick Volkerding cleaned up the SLS Linux distribution, in 1994, in support with Patrick Volkerding, Slackware scripts were translated into German, which was marked as the first release of S. u. S. E. It was available first on floppies, and then on CDs, for building its very own distribution of Linux, S. u. S. E used the jurix distribution as starting point. This was created by Florian La Roche, who joined the S. u. S. E team and he began to develop YaST, the installer and configuration tool that would become the central point of the distribution. In 1996, the first distribution under the name S. u. S. E Linux was published as S. u. S. E Linux 4.2. The version number has caused much discussion, it should have been just a version 1.1, yaSTs first version number,0.42, was a similar reference
33.
Scientific Linux
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Scientific Linux is a Linux distribution produced by Fermi National Accelerator Laboratory. It is a free and open source operating system based on Red Hat Enterprise Linux and this product is derived from the free and open source software made available by Red Hat, but is not produced, maintained or supported by them. It is built from the code for Red Hat Enterprise Linux versions, under the terms and conditions of Red Hat Enterprise Linuxs end-user license agreement. Fermilab already had a Linux distribution known as Fermi Linux, a long-term support release based on Red Hat Enterprise Linux, CERN was creating their next version of CERN Linux, also based on RHEL. CERN contacted Fermilab about doing a collaborative release, connie Sieh was the main developer and driver behind the first prototypes and initial release. The first official release of Scientific Linux was version 3.0.1, in 2015, CERN began migrating away from Scientific Linux to CentOS. Scientific Linux is now maintained by a cooperative of science labs, the primary purpose of Scientific Linux is to produce a common Linux distribution for various labs and universities around the world, thus reducing duplicated effort. The main goals are to have everything compatible with Red Hat Enterprise Linux with only minor additions and changes, the distribution is called Scientific Linux because it was initially made and used by scientific labs. It does not contain a collection of scientific software. However, it provides good compatibility to install such software, Scientific Linux is derived from Red Hat Enterprise Linux, with protected components, such as Red Hat trademarks, removed, thus making it freely available. New releases are produced about two months after each Red Hat release. As well as a full distribution equal to two DVDs, Scientific Linux is also available in LiveCD and LiveDVD versions and it also contains a set of tools for making custom versions, thus allowing institutions and individuals to create their own variant. Security updates are provided for as long as Red Hat continues to release updates and patches for their versions
34.
Linux distribution
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A Linux distribution is an operating system made from a software collection, which is based upon the Linux kernel and, often, a package management system. A typical Linux distribution comprises a Linux kernel, GNU tools and libraries, additional software, documentation, a system, a window manager. Most of the software is free and open-source software made available both as compiled binaries and in source code form, allowing modifications to the original software. Usually, Linux distributions optionally include some proprietary software that may not be available in source code form, the software is usually adapted to the distribution and then packaged into software packages by the distributions maintainers. The software packages are available online in so-called repositories, which are storage locations usually distributed around the world, almost six hundred Linux distributions exist, with close to five hundred out of those in active development. There are commercially backed distributions, such as Fedora, openSUSE and Ubuntu, most distributions come ready to use and pre-compiled for a specific instruction set, while some distributions are distributed mostly in source code form and compiled locally during installation. Linus Torvalds developed the Linux kernel and distributed its first version,0.01, since the installation procedure was complicated, especially in the face of growing amounts of available software, distributions sprang up to simplify this. Early distributions included the following, H. J, the SLS distribution was not well maintained, so in July 1993 a new distribution, called Slackware and based on SLS, was released by Patrick Volkerding. Also dissatisfied with SLS, Ian Murdock set to create a distribution by founding Debian. Most early adopters were familiar with Unix from work or school and they embraced Linux distributions for their low cost, and availability of the source code for most or all of the software included. Originally, the distributions were simply a convenience, but later became the usual choice even for Unix or Linux experts. To date, Linux has become popular in server and embedded devices markets than in the desktop market. For example, Linux is used on over 50% of web servers, many Linux distributions provide an installation system akin to that provided with other modern operating systems. Distributions are normally segmented into packages, each package contains a specific application or service. Examples of packages are a library for handling the PNG image format, the package is typically provided as compiled code, with installation and removal of packages handled by a package management system rather than a simple file archiver. Each package intended for such a PMS contains meta-information such as a description, version. Although Linux distributions typically contain much more software than proprietary operating systems, an example would be a newer version of a software application than that supplied with a distribution, or an alternative to that chosen by the distribution. If the additional software is distributed in form, this approach requires local compilation
35.
Fermilab
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Fermi National Accelerator Laboratory, located just outside Batavia, Illinois, near Chicago, is a United States Department of Energy national laboratory specializing in high-energy particle physics. Since 2007, Fermilab has been operated by the Fermi Research Alliance, a joint venture of the University of Chicago, Fermilab is a part of the Illinois Technology and Research Corridor. Fermilabs Tevatron was a particle accelerator, at 3.9 miles in circumference, it was the worlds fourth-largest particle accelerator. In 1995, the discovery of the top quark was announced by researchers who used the Tevatrons CDF, in addition to high-energy collider physics, Fermilab hosts fixed-target and neutrino experiments, such as MicroBooNE, NOνA and SeaQuest. Completed neutrino experiments include MINOS, MINOS+, MiniBooNE and SciBooNE, the MiniBooNE detector was a 40-foot diameter sphere containing 800 tons of mineral oil lined with 1,520 phototube detectors. An estimated 1 million neutrino events were recorded each year, SciBooNE sat in the same neutrino beam as MiniBooNE but had fine-grained tracking capabilities. In the public realm, Fermilab hosts many events, not only public science lectures and symposia. The site is open dawn to dusk to visitors who present valid photo identification. Asteroid 11998 Fermilab is named in honor of the laboratory, weston, Illinois, was a community next to Batavia voted out of existence by its village board in 1966 to provide a site for Fermilab. The laboratory was founded in 1967 as the National Accelerator Laboratory, the laboratorys first director was Robert Rathbun Wilson, under whom the laboratory opened ahead of time and under budget. Many of the sculptures on the site are of his creation and he is the namesake of the sites high-rise laboratory building, whose unique shape has become the symbol for Fermilab and which is the center of activity on the campus. After Wilson stepped down in 1978 to protest the lack of funding for the lab and it was under his guidance that the original accelerator was replaced with the Tevatron, an accelerator capable of colliding protons and antiprotons at a combined energy of 1.96 TeV. Lederman stepped down in 1989 and remains Director Emeritus, the science education center at the site was named in his honor. The later directors include, John Peoples,1989 to 1999 Michael S, as of 2014, the first stage in the acceleration process takes place in two ion sources which turn hydrogen gas into H− ions. A magnetron generates a plasma to form the ions near the metal surface, at the exit of RFQ, the beam is matched by medium energy beam transport into the entrance of the linear accelerator. The next stage of acceleration is linear particle accelerator and this stage consists of two segments. The first segment has 5 vacuum vessel for drift tubes, operating at 201 MHz, the second stage has 7 side-coupled cavities, operating at 805 MHz. At the end of linac, the particles are accelerated to 400 MeV, immediately before entering the next accelerator, the H− ions pass through a carbon foil, becoming H+ ions
36.
CERN
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The European Organization for Nuclear Research, known as CERN, is a European research organization that operates the largest particle physics laboratory in the world. Established in 1954, the organization is based in a northwest suburb of Geneva on the Franco–Swiss border, Israel is the only non-European country granted full membership. The main site at Meyrin hosts a large computing facility, which is used to store and analyse data from experiments. Researchers need remote access to facilities, so the lab has historically been a major wide area network hub. CERN is also the birthplace of the World Wide Web, the convention establishing CERN was ratified on 29 September 1954 by 12 countries in Western Europe. The acronym was retained for the new laboratory after the council was dissolved. CERNs first president was Sir Benjamin Lockspeiser, edoardo Amaldi was the general secretary of CERN at its early stages when operations were still provisional, while the first Director-General was Felix Bloch. The laboratory was originally devoted to the study of atomic nuclei, therefore, the laboratory operated by CERN is commonly referred to as the European laboratory for particle physics, which better describes the research being performed there. Several important achievements in physics have been made through experiments at CERN. The 1984 Nobel Prize for Physics was awarded to Carlo Rubbia, the 1992 Nobel Prize for Physics was awarded to CERN staff researcher Georges Charpak for his invention and development of particle detectors, in particular the multiwire proportional chamber. The World Wide Web began as a CERN project named ENQUIRE, initiated by Tim Berners-Lee in 1989, Berners-Lee and Cailliau were jointly honoured by the Association for Computing Machinery in 1995 for their contributions to the development of the World Wide Web. Based on the concept of hypertext, the project was intended to facilitate the sharing of information between researchers, the first website was activated in 1991. On 30 April 1993, CERN announced that the World Wide Web would be free to anyone, a copy of the original first webpage, created by Berners-Lee, is still published on the World Wide Web Consortiums website as a historical document. Prior to the Webs development, CERN had pioneered the introduction of Internet technology, a short history of this period can be found at CERN. ch. More recently, CERN has become a facility for the development of computing, hosting projects including the Enabling Grids for E-sciencE. It also hosts the CERN Internet Exchange Point, one of the two main internet exchange points in Switzerland. 48×10−5, a measurement with 6. 0-sigma significance. However, on 23 February, CERN stated in a release that the results were flawed due to an incorrectly connected GPS-synchronization cable. In March 2012, the ICARUS Collaboration reported that the measurement would be reproduced by both OPERA and ICARUS, further tests, after fixing the GPS connector, showed speed measurements consistent with the speed of light from four experiments at Gran Sasso, including OPERA
37.
Rocks Cluster Distribution
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Rocks Cluster Distribution is a Linux distribution intended for high-performance computing clusters. Rocks includes many tools which are not part of CentOS but are components that make a group of computers into a cluster. Installations can be customized with additional software packages at install-time by using special user-supplied CDs, over a dozen Rolls have been created, including the SGE roll, the Condor roll, the Lustre roll, the Java roll, and the Ganglia roll. By October 2010, Rocks was used for academic, government, the largest registered academic cluster, having 8632 CPUs, is GridKa, operated by the Karlsruhe Institute of Technology in Karlsruhe, Germany. There are also a number of clusters ranging down to fewer than 10 CPUs, representing the stages in the construction of larger systems
38.
386BSD
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386BSD, sometimes called Jolix, is a discontinued free Unix-like operating system based on BSD, first released in 1992. It ran on PC-compatible computer systems based on the 32-bit Intel 80386 microprocessor, 386BSD innovations include role-based security, ring buffers, self-ordered configuration and modular kernel design. The BSDs for PC descend from it, 386BSD was written mainly by Berkeley alumni Lynne Jolitz and William Jolitz. Work on porting 4. 3BSD-Reno and later 4. 3BSD Net/2 to the Intel 80386 was done for the University of California by William Jolitz at Berkeley,4. 3BSD Net/2 was an incomplete non-operational release, with portions withheld by the University of California as encumbered. The port began in 1989 and the first, incomplete traces of the port can be found in 4. 3BSD Net/2 of 1991 and it was first released in March 1992 and in a much more usable version on July 14,1992. The porting process with code was extensively documented in an 18-part series written by Lynne Jolitz, after the release of 386BSD0.1, a group of users began collecting bug fixes and enhancements, releasing them as an unofficial patchkit. Around the same time, the NetBSD project was founded by a different group of 386BSD users, both projects continue to this day. There has never been any legal filings or claims from the University, USL, finally, no code developed for 386BSD done by William Jolitz and Lynne Jolitz was at issue in any of these lawsuits. In late 1994, a finished version 386BSD Release 1.0 was distributed by Dr. Dobbs Journal on CDROM only due to the size of the release and was a best-selling CDROM for three years. On August 5,2016 an update was pushed to the 386BSD github by developer Ben Jolitz, however, as of March 16,2017, almost all of the documentation remains the same as version 1.0, and a change log was not available. 386BSD is often confused with BSD/386 which was a different project developed by BSDi, BSD/386 used the same 386BSD code contributed to the University of California on 4. 3BSD NET/2. Although Jolitz worked briefly for UUNET in 1991, the work he did for them diverged from that contributed to the University of California, all rights with respect to 386BSD and JOLIX are now held exclusively by William Jolitz and Lynne Jolitz. 386BSD public releases ended in 1997 since code is now available from the many 386BSD-derived operating systems today, portions of 386BSD may be found in other open systems such as OpenSolaris. Remarks on the history of 386BSD by Lynne Jolitz Remarks on the history of 386BSD by Greg Lehey More information on the releases of 386BSD Browsable 386BSD kernel sources
39.
FreeBSD
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FreeBSD is a free and open source Unix-like operating system descended from Research Unix via the Berkeley Software Distribution. Although for legal reasons FreeBSD cannot use the Unix trademark, it is a descendant of BSD. FreeBSD has similarities with Linux, with two differences in scope and licensing, FreeBSD maintains a complete operating system, i. e. The FreeBSD project includes a security team overseeing all software shipped in the base distribution, a wide range of additional third-party applications may be installed using the pkgng package management system or the FreeBSD Ports, or by directly compiling source code. FreeBSDs roots go back to the University of California, Berkeley, the university acquired a UNIX source license from AT&T. The BSD project was founded in 1976 by Bill Joy, but since BSD contained code from AT&T Unix, all recipients had to get a license from AT&T first in order to use BSD. In June 1989, Networking Release 1 or simply Net-1 – the first public version of BSD – was released, after releasing Net-1, Keith Bostic, a developer of BSD, suggested replacing all AT&T code with freely-redistributable code under the original BSD license. Work on replacing AT&T code began and, after 18 months, however, six files containing AT&T code remained in the kernel. The BSD developers decided to release the Networking Release 2 without those six files and they released 386BSD via an anonymous FTP server. The first version of FreeBSD was released on November 1993, in the early days of the projects inception, a company named Walnut Creek CDROM, upon the suggestion of the two FreeBSD developers, agreed to release the operating system on CD-ROM. By 1997, FreeBSD was Walnut Creeks most successful product, the company itself later renamed to The FreeBSD Mall and later iXSystems. Today, FreeBSD is used by many IT companies such as IBM, Nokia, Juniper Networks, certain parts of Apples Mac OS X operating system are based on FreeBSD. The PlayStation 3 operating system also borrows certain components from FreeBSD, netflix, WhatsApp, and FlightAware are also examples of big, successful and heavily network-oriented companies which are running FreeBSD. 386BSD and FreeBSD were both derived from 1992s BSD release, in January 1992, BSDi started to release BSD/386, later called BSD/OS, an operating system similar to FreeBSD and based on 1992s BSD release. AT&T filed a lawsuit against BSDi and alleged distribution of AT&T source code in violation of license agreements, the lawsuit was settled out of court and the exact terms were not all disclosed. The only one that became public was that BSDi would migrate their source base to the newer 4. 4BSD-Lite sources, Although not involved in the litigation, it was suggested to FreeBSD that they should also move to 4. 4BSD-Lite. FreeBSD2.0, which was released on November 1994, was the first version of FreeBSD without any code from AT&T, Desktop Although FreeBSD does not install the X Window System by default, it is available in the FreeBSD ports collection. A number of Desktop environments such as GNOME, KDE and Xfce, embedded systems Although it explicitly focuses on the IA-32 and x86-64 platforms, FreeBSD also supports others such as ARM, PowerPC and MIPS to a lesser degree
40.
NetBSD
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NetBSD is a free and open source Unix-like operating system that descends from Berkeley Software Distribution, a Research Unix derivative developed at the University of California, Berkeley. It was the second open-source BSD descendant formally released after it forked from the 386BSD branch of the BSD source-code repository. It continues to be developed and is available for many platforms, including large-scale server systems, desktop systems, and handheld devices. The NetBSD project focuses on code clarity, careful design, netBSDs source code is openly available and permissively licensed. The NetBSD project began as a result of frustration within the 386BSD developer community with the pace and they aimed to produce a unified, multi-platform, production-quality, BSD-based operating system. The name NetBSD was suggested by de Raadt, based on the importance and growth of such as the Internet at that time. The NetBSD source code repository was established on 21 March 1993 and this was derived from 386BSD0.1 plus the version 0.2.2 unofficial patchkit, with several programs from the Net/2 release missing from 386BSD re-integrated, and various other improvements. The first multi-platform release, NetBSD1.0, was made in October 1994, also in 1994, for disputed reasons, one of the founders, Theo de Raadt, was removed from the project. He later founded a new project, OpenBSD, from a version of NetBSD1.0 near the end of 1995. In 1998, NetBSD1.3 introduced the pkgsrc packages collection, until 2004, NetBSD1. x releases were made at roughly annual intervals, with minor patch releases in between. The previous minor releases are now divided into two categories, x. y stable maintenance releases and x. y. z releases containing only security, as the projects motto suggests, NetBSD has been ported to a large number of 32- and 64-bit architectures. These range from VAX minicomputers to Pocket PC PDAs, as of 2009, NetBSD supports 57 hardware platforms. The kernel and userland for these platforms are all built from a central unified source-code tree managed by CVS, currently, unlike other kernels such as μClinux, the NetBSD kernel requires the presence of an MMU in any given target architecture. NetBSDs portability is aided by the use of hardware abstraction layer interfaces for low-level hardware access such as bus input/output or DMA, using this portability layer, device drivers can be split into machine-independent and machine-dependent components. This makes a single driver easily usable on several platforms by hiding hardware access details, and reduces the work to port it to a new system. This permits a device driver for a PCI card to work without modifications, whether its in a PCI slot on an IA-32, Alpha, PowerPC, SPARC. Also, a driver for a specific device can operate via several different buses, like ISA, PCI. In comparison, Linux device driver code often must be reworked for each new architecture, as a consequence, in porting efforts by NetBSD and Linux developers, NetBSD has taken much less time to port to new hardware
41.
OpenBSD
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OpenBSD is a free and open source Unix-like computer operating system descended from Berkeley Software Distribution, a Research Unix derivative developed at the University of California, Berkeley. In late 1995, Theo de Raadt forked it from NetBSD, besides the operating system as a whole, the project maintains portable versions of many subsystems, most notably OpenSSH, which are available as packages in other operating systems. The project is known for its developers insistence on open-source code, good documentation, code correctness and it has strict policies on licensing, preferring the ISC license and other variants of the Simplified BSD License. Many of its security features are optional or absent in other operating systems and its developers frequently audit the source tree for software bugs and security holes. De Raadt coordinates the project from his home in Calgary, Alberta and its logo and mascot is a pufferfish named Puffy. In December 1994, NetBSD co-founder Theo de Raadt was asked to resign from his position as a developer and member of the NetBSD core team. The reason for this is not wholly clear, although there are claims that it was due to personality clashes within the NetBSD project, in October 1995, de Raadt founded OpenBSD, a new project forked from NetBSD1.0. The initial release, OpenBSD1.2, was made in July 1996, since then, the project has followed a schedule of a release every six months, each of which is supported for one year. Just how widely OpenBSD is used is hard to determine as its developers do not publish or collect usage statistics. OpenBSDs security enhancements, built-in cryptography, and the pf packet filter suit it for use in the security industry, such as on firewalls, intrusion-detection systems, and VPN gateways. Proprietary systems from several manufacturers are based on OpenBSD, including devices from Armorlogic, Calyptix Security, GeNUA, RTMX, later versions of Microsofts Services for UNIX, an extension to the Windows operating system providing Unix-like functionality, use large amounts of OpenBSD code. OpenBSD ships with the X Window System and is suitable for use on the desktop, packages are available for popular applications, including desktop environments such as GNOME, KDE, and Xfce, and web browsers such as Firefox and Chromium. The project also includes three window managers in the distribution, cwm, FVWM, and twm. OpenBSD used to include a fork of Apache 1.3, in the 5.6 release, Nginx was replaced with httpd, an HTTP server with FastCGI and Transport Layer Security support. As of May 2016, Apache and Nginx are still available as ports, development is continuous, and team management is open and tiered. Snapshot releases are available at frequent intervals. Maintenance patches for supported releases may be applied manually or by updating the system against the branch of the CVS repository for that release. The standard OpenBSD kernel, as maintained by the project, is recommended for end users
42.
DragonFly BSD
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DragonFly BSD is a free and open source Unix-like operating system created as a fork of FreeBSD4.8. He sought to correct these problems within the FreeBSD project. Due to ongoing conflicts with other FreeBSD developers over the implementation of his ideas, despite this, the DragonFly BSD and FreeBSD projects still work together contributing bug fixes, driver updates, and other system improvements to each other. Intended to be the continuation of the FreeBSD4. Many concepts planned for DragonFly were inspired by the AmigaOS operating system, the messaging subsystem being developed is similar to those found in microkernels such as Mach, though it is less complex by design. Additionally, the migration of select kernel code into userspace has the benefit of making the more robust, if a userspace driver crashes. System calls are being split into userland and kernel versions and being encapsulated into messages, Linux and other Unix-like OS compatibility code is being migrated out similarly. As support for multiple instruction set architectures complicates symmetric multiprocessing support, DragonFly originally ran on the x86 architecture, however as of version 4.0 it is no longer supported. Since version 1.10, DragonFly supports 1,1 userland threading, inherited from FreeBSD, DragonFly also supports multi-threading. In DragonFly, each CPU has its own thread scheduler, inter-processor thread scheduling is also accomplished by sending asynchronous IPI messages. The LWKT subsystem is being employed to work among multiple kernel threads. In order to run safely on multiprocessor machines, access to shared resources must be serialized so that threads or processes do not attempt to modify the same resource at the same time. In order to prevent multiple threads from accessing or modifying a shared resource simultaneously, DragonFly employs critical sections, while both Linux and FreeBSD5 employ fine-grained mutex models to achieve higher performance on multiprocessor systems, DragonFly does not. Until recently, DragonFly also employed spls, but these were replaced with critical sections, critical sections are used to protect against local interrupts, individually for each CPU, guaranteeing that a thread currently being executed will not be preempted. Serializing tokens are used to prevent concurrent accesses from other CPUs and may be held simultaneously by multiple threads, blocked or sleeping threads therefore do not prevent other threads from accessing the shared resource unlike a thread that is holding a mutex. The serializing token code is evolving into something similar to the Read-copy-update feature now available in Linux. Unlike Linuxs current RCU implementation, DragonFlys is being implemented such that only processors competing for the same token are affected rather than all processors in the computer, DragonFly switched to multiprocessor safe slab allocator, which requires neither mutexes nor blocking operations for memory assignment tasks. It was eventually ported into standard C library in the userland, since release 1.8 DragonFly has a virtualization mechanism similar to User-mode Linux, allowing a user to run another kernel in the userland
43.
NeXTSTEP
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NeXTSTEP is a discontinued object-oriented, multitasking operating system based on UNIX. Although relatively unsuccessful at the time, it attracted interest from computer scientists and it was also the platform on which Tim Berners-Lee created the first web browser. After the purchase of NeXT by Apple, it became the source of the operating systems macOS, iOS, watchOS and tvOS. Many bundled macOS applications, such as TextEdit, Mail and Chess, are descendants of NeXTSTEP applications, the toolkits offer considerable power, and are the canonical development system for all of the software on the machine. NeXTSTEPs user interface is considered to be refined and consistent and it introduced the idea of the Dock and the Shelf. Additional kits were added to the line to make the system more attractive. These include Portable Distributed Objects, which allow easy remote invocation, and Enterprise Objects Framework, the kits made the system particularly interesting to custom application programmers, and NeXTSTEP had a long history in the financial programming community. A preview release of NeXTSTEP was shown with the launch of the NeXT Computer on October 12,1988, the first full release, NeXTSTEP1.0, shipped on September 18,1989. NeXTSTEP was later modified to separate the underlying operating system from the higher-level object libraries, the result was the OpenStep API, which ran on multiple underlying operating systems, including NeXTs own OPENSTEP, Windows NT and SUN Solaris. NeXTSTEPs legacy stands today in the form of its direct descendents, from day one, the operating system of NeXTSTEP was built upon Mach/BSD. It was built on 4. 3BSD Tahoe and it changed to 4. 3BSD Reno after the release of NeXTSTEP3.0. It changed to 4. 4BSD during the development of Rhapsody, the first web browser, WorldWideWeb, and the first ever app store were all invented on the NeXTSTEP platform. Some features and keyboard shortcuts now commonly found in web browsers can be traced back to NeXTSTEP conventions, the basic layout options of HTML1.0 and 2.0 are attributable to those features available in NeXTs Text class. Other games based on the Doom engine such as Heretic and its sequel Hexen by Raven Software as well as Strife by Rogue Entertainment were also developed on NeXT hardware using ids tools. Altsys made a NeXTSTEP application called Virtuoso, version 2 of which was ported to Mac OS, the modern Notebook interface for Mathematica, and the advanced spreadsheet Lotus Improv, were developed using NeXTSTEP. The software that controlled MCIs Friends and Family calling plan program was developed using NeXTSTEP, about the time of the release of NeXTSTEP3.2, NeXT partnered with Sun Microsystems to develop OpenStep. It is the product of an effort to separate the underlying operating system from the higher-level object libraries to create a cross-platform object-oriented API standard derived from NeXTSTEP, the OpenStep API targets multiple underlying operating systems, including NeXTs own OPENSTEP. Implementations of that standard were released for Suns Solaris, Windows NT, NeXTs implementation is called OPENSTEP for Mach and its first release superseded NeXTSTEP3.3 on NeXT, Sun and Intel IA-32 systems
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Darwin (operating system)
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Darwin is an open-source Unix operating system released by Apple Inc. in 2000. It is composed of code developed by Apple, as well as derived from NeXTSTEP, BSD, Mach. Darwin forms the set of components upon which macOS, iOS, watchOS. It is mostly POSIX-compatible, but has never, by itself, starting with Leopard, macOS has been certified as compatible with the Single UNIX Specification version 3. The heritage of Darwin began with NeXTs NeXTSTEP operating system, first released in 1989, after Apple bought NeXT in 1997, it announced it would base its next operating system on OPENSTEP. This was developed into Rhapsody in 1997, Mac OS X Server 1.0 in 1999, Mac OS X Public Beta in 2000, and Mac OS X10.0 in 2001. Up to Darwin 8.0.1, Apple released a binary installer after each major Mac OS X release that one to install Darwin on PowerPC. Minor updates were released as packages that were installed separately, Darwin is now only available as source code, except for the ARM variant, which has not been released in any form separately from iOS. However, the versions of Darwin are still available in binary form. The kernel of Darwin is XNU, a kernel that combines a heavily modified version of the Mach 3.0 kernel, various elements of BSD. The hybrid kernel design leverages the flexibility of a microkernel and the performance of a monolithic kernel. An open-source port of the XNU kernel exists that supports Darwin on Intel and AMD x86 platforms not officially supported by Apple, an open-source port of the XNU kernel also exists for ARM platforms. Older versions supported some or all of 32-bit PowerPC, 64-bit PowerPC and it supports the POSIX API by way of its BSD lineage and a large number of programs written for various other UNIX-like systems can be compiled on Darwin with no changes to the source code. Darwin does not include many of the elements of macOS, such as the Carbon and Cocoa APIs or the Quartz Compositor and Aqua user interface. The following is a table of major Darwin releases with their dates of release, note that the corresponding macOS release may have been released on a different date, refer to the macOS pages for those dates. In the build numbering system of macOS, every version has a unique beginning build number, Mac OS X v10.0 had build numbers starting with 4,10.1 had build numbers starting with 5, and so forth. The command uname -r in Terminal will show the Darwin version number, and the command uname -v will show the XNU build version string, due to the free software nature of Darwin, there are many projects that aim to modify or enhance the operating system. OpenDarwin was an operating system based on the Darwin system
