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DFSORT
The Sort/Merge utility is a mainframe program to sort records in a file into a specified order, merge pre-sorted files into a sorted file, or copy selected records. Internally, these utilities use one or more of the standard sorting algorithms, often with proprietary fine-tuned code. Mainframes were originally supplied with limited main memory by today's standards and the amount of data to be sorted was frequently very large. Because of this, unlike more recent sort programs, early Sort/Merge programs placed great emphasis on efficient techniques for sorting data on secondary storage, typically tape or disk. In 1968 the OS/360 Sort/Merge program provided five different "sequence distribution techniques" that could be used depending on the number and type of devices available. Prior to the System/370, all IBM mainframe operating systems included sort/merge utilities. With the announcement of virtual storage operating systems, DOS/VS and OS/VS, IBM unbundled much of the softw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM Mainframe Utility Programs
This article discusses support programs included in or available for OS/360 and successors. IBM categorizes some of these programs as utilities and others as service aids; the boundaries are not always consistent or obvious. Many, but not all, of these programs match the types in utility software. The following lists describe programs associated with OS/360 and successors. No DOS, TPF or VM utilities are included. History/Common JCL Many of these programs were designed by IBM users, through the group SHARE, and then modified or extended by IBM from versions originally written by a user. These programs are usually invoked via Job Control Language (JCL). They tend to use common JCL DD identifiers (in the OS, now z/OS operating systems) for their data sets: Dataset utilities IDCAMS IDCAMS ("Access Method Services") generates and modifies Virtual Storage Access Method (VSAM) and Non-VSAM datasets. IDCAMS was introduced along with VSAM in OS/VS; the "Access Method" reference deri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BatchPipes
On IBM mainframes, BatchPipes is a batch job processing utility which runs under the MVS/ESA operating system and later versions—OS/390 and z/OS. Core function In traditional processing, if data records are written out to sequential (QSAM and BSAM) data set on disk or tape, they cannot be read concurrently by another job. The "writer" and "reader" cannot run at the same time. This is termed ''file-level interlock'' or ''data-set-level interlock''. With BatchPipes an installation can arrange for the data to be "piped" between the two jobs. The advantage is that the jobs can run concurrently and it is possible, and very usual, to avoid the time to write the data to secondary storage and to read it back. The combination of these two characteristics, if used judiciously, leads to a reduction in the combined elapsed time of the two jobs, as measured from the start of the writer job to the end of the reader job. BatchPipes maintains a ''short'' queue of records being passed betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operating Systems
An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting software for cost allocation of processor time, mass storage, printing, and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computer from cellular phones and video game consoles to web servers and supercomputers. The dominant general-purpose personal computer operating system is Microsoft Windows with a market share of around 74.99%. macOS by Apple Inc. is in second place (14.84%), and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
External Sort
External sorting is a class of sorting algorithms that can handle massive amounts of data. External sorting is required when the data being sorted do not fit into the main memory of a computing device (usually RAM) and instead they must reside in the slower Auxiliary memory, external memory, usually a disk drive. Thus, external sorting algorithms are external memory algorithms and thus applicable in the external memory model, external memory model of computation. External sorting algorithms generally fall into two types, distribution sorting, which resembles quicksort, and external merge sort, which resembles merge sort. The latter typically uses a hybrid algorithm, hybrid sort-merge strategy. In the sorting phase, chunks of data small enough to fit in main memory are read, sorted, and written out to a temporary file. In the merge phase, the sorted subfiles are combined into a single larger file. Model External sorting algorithms can be analyzed in the external memory model. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM Drum Storage
In addition to the drums used as main memory by IBM, e.g., IBM 305, IBM 650, IBM offered drum devices as secondary storage for the 700/7000 series and System/360 series of computers. IBM 731 The IBM 731 is a discontinued storage unit used on the IBM 701. It has a storage capacity of 2048 36-bit words (9,216 8-bit bytes). IBM 732 The IBM 732 is a discontinued storage unit used on the IBM 702. It has a storage capacity of 60,000 6-bit characters (45,000 8-bit bytes). IBM 733 The IBM 733 is a discontinued storage unit used on the IBM 704 and IBM 709. It has a storage capacity of 8192 36-bit words (36,864 8-bit bytes). IBM 734 The IBM 734 is a discontinued storage unit used on the IBM 705 It has a storage capacity of 60,000 6-bit characters (45,000 8-bit bytes). IBM 7320 The IBM 7320 is a discontinued storage unit manufactured by IBM announced on December 10, 1962 for the IBM 7090 and 7094 computer systems, was retained for the earliest System/360 systems as a count key data ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 2311
IBM manufactured magnetic disk storage devices from 1956 to 2003, when it sold its hard disk drive business to Hitachi. Both the hard disk drive (HDD) and floppy disk drive (FDD) were invented by IBM and as such IBM's employees were responsible for many of the innovations in these products and their technologies. The basic mechanical arrangement of hard disk drives has not changed since the IBM 1301. Disk drive performance and characteristics are measured by the same standards now as they were in the 1950s. Few products in history have enjoyed such spectacular declines in cost and physical size along with equally dramatic improvements in capacity and performance. IBM manufactured 8-inch floppy disk drives from 1969 until the mid-1980s, but did not become a significant manufacturer of smaller-sized, 5.25- or 3.5-inch floppy disk drives (the dimension refers to the diameter of the floppy disk, not the size of the drive). IBM always offered its magnetic disk drives for sale but did no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micro Focus
Micro Focus International plc is a British multinational software and information technology business based in Newbury, Berkshire, England. The firm provides software and consultancy. The company is listed on the London Stock Exchange and is a constituent of the FTSE 250 Index. History Micro Focus was founded in 1976. In 1981, it became the first company to win the Queen's Award for Industry purely for developing a software product. The product was CIS COBOL, a standard-compliant COBOL implementation for microcomputers. In 1998, the company acquired Intersolv Inc, an applications enablement business, for and the combined business was renamed Merant. The same year the company acquired XDB Systems with their XDB Enterprise Server relational database management system. In 2001 the business was demerged from Merant with help from Golden Gate Capital Partners and once again became Micro Focus. It was listed on the London Stock Exchange in 2005. In May 2007, San Diego-based Acu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft Windows
Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for servers, and Windows IoT for embedded systems. Defunct Windows families include Windows 9x, Windows Mobile, and Windows Phone. The first version of Windows was released on November 20, 1985, as a graphical operating system shell for MS-DOS in response to the growing interest in graphical user interfaces (GUIs). Windows is the most popular desktop operating system in the world, with 75% market share , according to StatCounter. However, Windows is not the most used operating system when including both mobile and desktop OSes, due to Android's massive growth. , the most recent version of Windows is Windows 11 for consumer PCs and tablets, Windows 11 Enterprise for corporations, and Windows Server 2022 for servers. Genealogy By marketing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linux
Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which includes the kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name "GNU/Linux" to emphasize the importance of GNU software, causing some controversy. Popular Linux distributions include Debian, Fedora Linux, and Ubuntu, the latter of which itself consists of many different distributions and modifications, including Lubuntu and Xubuntu. Commercial distributions include Red Hat Enterprise Linux and SUSE Linux Enterprise. Desktop Linux distributions include a windowing system such as X11 or Wayland, and a desktop environment such as GNOME or KDE Plasma. Distributions intended for ser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix
Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors including University of California, Berkeley (Berkeley Software Distribution, BSD), Microsoft (Xenix), Sun Microsystems (SunOS/Solaris (operating system), Solaris), Hewlett-Packard, HP/Hewlett Packard Enterprise, HPE (HP-UX), and IBM (IBM AIX, AIX). In the early 1990s, AT&T sold its rights in Unix to Novell, which then sold the UNIX trademark to The Open Group, an industry consortium founded in 1996. The Open Group allows the use of the mark for certified operating systems that comply with the Single UNIX Specification (SUS). Unix systems are chara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CA Technologies
CA Technologies, formerly known as CA, Inc. and Computer Associates International, Inc., is an American multinational corporation headquartered in New York City. It is primarily known for its business-to-business (B2B) software with a product portfolio focused on Agile software development, DevOps, and computer security software spanning across a wide range of environments such as a mainframe, distributed computing, cloud computing, and mobile devices. The company markets nearly 200 software products. Some of the best-known are ACF2 (security), TopSecret (security), Datacom (database), Easytrieve (report generator), IDMS (database), InterTest (debugging), Librarian, Panvalet (source code library management), and TLMS (tape library management). Through 2018, CA Technologies maintained offices in more than 40 countries and employed approximately 11,300 people. CA holds more than 1,500 patents worldwide, and has more than 900 patent applications pending. It was headquartered on Lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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