IBM mainframes are large computer systems produced by
IBM since 1952. During the 1960s and 1970s, IBM dominated the large computer market. Current
mainframe computer
A mainframe computer, informally called a mainframe or big iron, is a computer used primarily by large organizations for critical applications like bulk data processing for tasks such as censuses, industry and consumer statistics, enterpris ...
s in IBM's line of business computers are developments of the basic design of the IBM
System/360
The IBM System/360 (S/360) is a family of mainframe computer systems that was announced by IBM on April 7, 1964, and delivered between 1965 and 1978. It was the first family of computers designed to cover both commercial and scientific applica ...
.
First and second generation
![IBM Electronic Data Processing Machine - GPN-2000-001881](https://upload.wikimedia.org/wikipedia/commons/2/20/IBM_Electronic_Data_Processing_Machine_-_GPN-2000-001881.jpg)
From 1952 into the late 1960s, IBM manufactured and marketed several large computer models, known as the
IBM 700/7000 series
The IBM 700/7000 series is a series of large-scale (Mainframe computer, mainframe) computer systems that were made by IBM through the 1950s and early 1960s. The series includes several different, incompatible processor architectures. The 700s ...
. The first-generation 700s were based on
vacuum tube
A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied.
The type kn ...
s, while the later, second-generation 7000s used
transistor
upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink).
A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch e ...
s. These machines established IBM's dominance in
electronic data processing ("EDP"). IBM had two model categories: one (701, 704, 709, 7030, 7090, 7094, 7040, 7044) for engineering and scientific use, and one (702, 705, 705-II, 705-III, 7080, 7070, 7072, 7074, 7010) for commercial or data processing use. The two categories, scientific and commercial, generally used common peripherals but had completely different
instruction set
In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer. A device that executes instructions described by that ISA, such as a central processing unit (CPU), is called an ' ...
s, and there were incompatibilities even within each category.
IBM initially sold its computers without any software, expecting customers to write their own; programs were manually initiated, one at a time. Later, IBM provided
compilers
In computing, a compiler is a computer program that translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primarily used for programs that ...
for the newly developed higher-level
programming language
A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language.
The description of a programming ...
s
Fortran,
COMTRAN
COMTRAN (COMmercial TRANslator) is an early programming language developed at IBM. It was intended as the business programming equivalent of the scientific programming language FORTRAN (FORmula TRANslator). It served as one of the forerunners ...
and later
COBOL
COBOL (; an acronym for "common business-oriented language") is a compiled English-like computer programming language designed for business use. It is an imperative, procedural and, since 2002, object-oriented language. COBOL is primarily us ...
. The first
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 inc ...
for IBM computers were written by IBM customers who did not wish to have their very expensive machines ($2M USD in the mid-1950s) sitting idle while operators set up jobs manually. These first operating systems were essentially scheduled work queues. It is generally thought that the first operating system used for real work was
GM-NAA I/O
The GM-NAA I/O input/output system of General Motors and North American Aviation was the first operating system for the IBM 704 computer.
It was created in 1956 by Robert L. Patrick of General Motors Research and Owen Mock of North American Av ...
, produced by
General Motors
The General Motors Company (GM) is an American Multinational corporation, multinational Automotive industry, automotive manufacturing company headquartered in Detroit, Michigan, United States. It is the largest automaker in the United States and ...
' Research division in 1956. IBM enhanced one of GM-NAA I/O's successors, the
SHARE Operating System
The SHARE Operating System (SOS) is an operating system introduced in 1959 by the SHARE user group. It is an improvement on the General Motors GM-NAA I/O operating system, the first operating system for the IBM 704. The main objective was to im ...
, and provided it to customers under the name
IBSYS
IBSYS is the discontinued tape-based operating system that IBM supplied with its IBM 709, IBM 7090 and IBM 7094 computers. A similar operating system (but with several significant differences), also called IBSYS, was provided with IBM 7040 and ...
.
As software became more complex and important, the cost of supporting it on so many different designs became burdensome, and this was one of the factors which led IBM to develop
System/360
The IBM System/360 (S/360) is a family of mainframe computer systems that was announced by IBM on April 7, 1964, and delivered between 1965 and 1978. It was the first family of computers designed to cover both commercial and scientific applica ...
and its operating systems.
[
]
The second generation (transistor-based) products were a mainstay of IBM's business and IBM continued to make them for several years after the introduction of the System/360. (Some
IBM 7094
The IBM 7090 is a second-generation transistorized version of the earlier IBM 709 vacuum tube mainframe computer that was designed for "large-scale scientific and technological applications". The 7090 is the fourth member of the IBM 700/7000 ser ...
s remained in service into the 1980s.)
Smaller machines
![IBM 1401 signal tracing at CHM](https://upload.wikimedia.org/wikipedia/commons/6/66/IBM_1401_signal_tracing_at_CHM.jpg)
Prior to System/360, IBM also sold computers smaller in scale that were not considered mainframes, though they were still bulky and expensive by modern standards. These included:
*
IBM 650
The IBM 650 Magnetic Drum Data-Processing Machine is an early digital computer produced by IBM in the mid-1950s. It was the first mass produced computer in the world. Almost 2,000 systems were produced, the last in 1962, and it was the first ...
(vacuum tube logic,
decimal architecture
Decimal computers are computers which can represent numbers and addresses in decimal as well as providing instructions to operate on those numbers and addresses directly in decimal, without conversion to a pure binary representation. Some also ha ...
,
drum memory
Drum memory was a magnetic data storage device invented by Gustav Tauschek in 1932 in Austria. Drums were widely used in the 1950s and into the 1960s as computer memory.
For many early computers, drum memory formed the main working memory ...
, business and scientific)
*
IBM 305 RAMAC
The IBM 305 RAMAC was the first commercial computer that used a moving-head hard disk drive (magnetic disk storage) for secondary storage. The system was publicly announced on September 14, 1956, (vacuum tube logic, first computer with
disk storage
Disk storage (also sometimes called drive storage) is a general category of storage mechanisms where data is recorded by various electronic, magnetic, optical, or mechanical changes to a surface layer of one or more rotating disks. A disk drive is ...
; ''see:''
Early IBM disk storage
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 fo ...
)
*
IBM 1400 series
The IBM 1400 series were second-generation (transistor) mid-range business decimal computers that IBM marketed in the early 1960s. The computers were offered to replace tabulating machines like the IBM 407. The 1400-series machines stored infor ...
(business data processing; very successful and many 1400 peripherals were used with the 360s)
*
IBM 1620
The IBM 1620 was announced by IBM on October 21, 1959, and marketed as an inexpensive scientific computer. After a total production of about two thousand machines, it was withdrawn on November 19, 1970. Modified versions of the 1620 were used as ...
(decimal architecture, engineering, scientific, and education)
IBM had difficulty getting customers to upgrade from the smaller machines to the mainframes because so much software had to be rewritten. The 7010 was introduced in 1962 as a mainframe-sized 1410. The later Systems 360 and 370 could emulate the 1400 machines. A desk-size machine with a different instruction set, the
IBM 1130
The IBM 1130 Computing System, introduced in 1965, was IBM's least expensive computer at that time. A binary 16-bit machine, it was marketed to price-sensitive, computing-intensive technical markets, like education and engineering, succeeding th ...
, was released concurrently with the System/360 to address the niche occupied by the 1620. It used the same
EBCDIC
Extended Binary Coded Decimal Interchange Code (EBCDIC; ) is an eight-bit character encoding used mainly on IBM mainframe and IBM midrange computer operating systems. It descended from the code used with punched cards and the corresponding six- ...
character encoding as the 360 and was mostly programmed in
Fortran, which was relatively easy to adapt to larger machines when necessary.
IBM also introduced smaller machines after S/360. These included:
*
IBM System/7
The IBM System/7 was a computer system designed for industrial control, announced on October 28, 1970 and first shipped in 1971. It was a 16-bit machine and one of the first made by IBM to use novel semiconductor memory, instead of magnetic core m ...
(semiconductor memory, process control, incompatible replacement for
IBM 1800
The IBM 1800 Data Acquisition and Control System (DACS) was a process control variant of the IBM 1130 with two extra instructions (CMP and DCM), extra I/O capabilities, 'selector channel like' cycle-stealing capability and three hardware index regi ...
*
IBM Series/1
The IBM Series/1 is a 16-bit minicomputer, introduced in 1976, that in many respects competed with other minicomputers of the time, such as the PDP-11 from Digital Equipment Corporation and similar offerings from Data General and HP. The Seri ...
*
IBM 3790 The IBM 3790 Communications System was one of the first distributed computing platforms. The 3790 was developed by IBM's Data Processing Division (DPD) and announced in 1974. It preceded the IBM 8100, announced in 1979.
It was designed to be insta ...
*
IBM 8100
The IBM 8100 Information System, announced Oct. 3, 1978, was at one time IBM’s principal distributed processing engine, providing local processing capability under two incompatible operating systems ( DPPX and DPCX) and was a follow-on to the ...
*
IBM System/3
The IBM System/3 was an IBM midrange computer introduced in 1969, and marketed until 1985. It was produced by IBM Rochester in Minnesota as a low-end business computer aimed at smaller organizations that still used IBM 1400 series computers or u ...
(Introduced 96 column card)
''Midrange computer'' is a designation used by IBM for a class of computer systems which fall in between mainframes and microcomputers.
IBM System/360
![IBM system 360-50 console - MfK Bern](https://upload.wikimedia.org/wikipedia/commons/3/39/IBM_system_360-50_console_-_MfK_Bern.jpg)
All that changed with the announcement of the System/360 (S/360) in April, 1964. The System/360 was a single series of compatible models for both commercial and scientific use. The number "
360 360 may refer to:
* 360 (number)
* 360 AD, a year
* 360 BC, a year
* 360 degrees, a circle
Businesses and organizations
* 360 Architecture, an American architectural design firm
* Ngong Ping 360, a tourism project in Lantau Island, Hong Kong
* Q ...
" suggested a "360
degree
Degree may refer to:
As a unit of measurement
* Degree (angle), a unit of angle measurement
** Degree of geographical latitude
** Degree of geographical longitude
* Degree symbol (°), a notation used in science, engineering, and mathematics
...
," or "all-around" computer system. System/360 incorporated features which had previously been present on only either the commercial line (such as decimal arithmetic and byte addressing) or the engineering and scientific line (such as
floating-point arithmetic
In computing, floating-point arithmetic (FP) is arithmetic that represents real numbers approximately, using an integer with a fixed precision, called the significand, scaled by an integer exponent of a fixed base. For example, 12.345 can be ...
). Some of the arithmetic units and addressing features were optional on some models of the System/360. However, models were upward compatible and most were also downward compatible. The System/360 was also the first computer in wide use to include dedicated hardware provisions for the use of
operating system
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 in ...
s. Among these were supervisor and application mode programs and instructions, as well as built-in memory protection facilities. Hardware memory protection was provided to protect the operating system from the user programs (tasks) and user tasks from each other. The new machine also had a larger
address space
In computing, an address space defines a range of discrete addresses, each of which may correspond to a network host, peripheral device, disk sector, a memory cell or other logical or physical entity.
For software programs to save and retrieve st ...
than the older mainframes, 24 bits addressing 8-bit bytes vs. a typical 18 bits addressing 36-bit words.
The smaller models in the System/360 line (e.g. the 360/30) were intended to replace the 1400 series while providing an easier upgrade path to the larger 360s. To smooth the transition from the second generation to the new line, IBM used the 360's
microprogramming
In processor design, microcode (μcode) is a technique that interposes a layer of computer organization between the central processing unit (CPU) hardware and the programmer-visible instruction set architecture of a computer. Microcode is a laye ...
capability to emulate the more popular older models. Thus 360/30s with this added cost feature could run 1401 programs and the larger 360/65s could run 7094 programs. To run old programs, the 360 had to be halted and restarted in emulation mode. Many customers kept using their old software and one of the features of the later System/370 was the ability to switch to emulation mode and back under operating system control.
Operating systems for the System/360 family included
OS/360
OS/360, officially known as IBM System/360 Operating System, is a discontinued batch processing operating system developed by IBM for their then-new System/360 mainframe computer, announced in 1964; it was influenced by the earlier IBSYS/IBJOB ...
(with PCP, MFT, and
MVT),
BOS/360
Basic Operating System/360 (BOS/360) was an early IBM System/360 operating system.
Origin
BOS was one of four System/360 Operating System versions developed by the IBM General Products Division (GPD) in Endicott, New York to fill a gap at th ...
,
TOS/360, and
DOS/360
Disk Operating System/360, also DOS/360, or simply DOS, is the discontinued first member of a sequence of operating systems for IBM System/360, System/370 and later mainframes. It was announced by IBM on the last day of 1964, and it was first d ...
.
The System/360 later evolved into the
System/370
The IBM System/370 (S/370) is a model range of IBM mainframe computers announced on June 30, 1970, as the successors to the System/360 family. The series mostly maintains backward compatibility with the S/360, allowing an easy migration path f ...
, the
System/390
The IBM System/390 is a discontinued mainframe product family implementing the ESA/390, the fifth generation of the System/360 instruction set architecture. The first computers to use the ESA/390 were the Enterprise System/9000 (ES/90 ...
, and the
64-bit
In computer architecture, 64-bit Integer (computer science), integers, memory addresses, or other Data (computing), data units are those that are 64 bits wide. Also, 64-bit central processing unit, CPUs and arithmetic logic unit, ALUs are those ...
zSeries, System z, and zEnterprise machines. System/370 introduced
virtual memory
In computing, virtual memory, or virtual storage is a memory management technique that provides an "idealized abstraction of the storage resources that are actually available on a given machine" which "creates the illusion to users of a very l ...
capabilities in all models other than the very first System/370 models; the
OS/VS1
Operating System/Virtual Storage 1, or OS/VS1, is a discontinued IBM mainframe computer operating system designed to be run on IBM System/370 hardware. It was the successor to the OS/360 and successors#MFT, Multiprogramming with a Fixed number of ...
variant of OS/360 MFT, the
OS/VS2 (SVS)
Single Virtual Storage (SVS) refers to Release 1 of Operating System/Virtual Storage 2 (OS/VS2); it is the successor system to the MVT option of Operating System/360. OS/VS2 (SVS) was a stopgap measure pending the availability of MVS, although ...
variant of OS/360 MVT, and the DOS/VS variant of DOS/360 were introduced to use the virtual memory capabilities, followed by
MVS
Multiple Virtual Storage, more commonly called MVS, was the most commonly used operating system on the System/370 and System/390 IBM mainframe computers. IBM developed MVS, along with OS/VS1 and SVS, as a successor to OS/360. It is unrelated ...
, which, unlike the earlier virtual-memory operating systems, ran separate programs in separate address spaces, rather than running all programs in a single virtual address space. The virtual memory capabilities also allowed the system to support
virtual machine
In computing, a virtual machine (VM) is the virtualization/emulation of a computer system. Virtual machines are based on computer architectures and provide functionality of a physical computer. Their implementations may involve specialized hardw ...
s; the
VM/370
VM (often: VM/CMS) is a family of IBM virtual machine operating systems used on IBM mainframes System/370, System/390, zSeries, System z and compatible systems, including the Hercules emulator for personal computers.
The following versions ...
hypervisor
A hypervisor (also known as a virtual machine monitor, VMM, or virtualizer) is a type of computer software, firmware or hardware that creates and runs virtual machines. A computer on which a hypervisor runs one or more virtual machines is calle ...
would run one or more virtual machines running either standard System/360 or System/370 operating systems or the single-user
Conversational Monitor System
The Conversational Monitor System (CMS – originally: "Cambridge Monitor System") is a simple interactive single-user operating system. CMS was originally developed as part of IBM's CP/CMS operating system, which went into production use in ...
(CMS). A
time-sharing
In computing, time-sharing is the sharing of a computing resource among many users at the same time by means of multiprogramming and multi-tasking.DEC Timesharing (1965), by Peter Clark, The DEC Professional, Volume 1, Number 1
Its emergence a ...
VM system could run multiple virtual machines, one per user, with each virtual machine running an instance of CMS.
Today's systems
![Z800 2066 JKU](https://upload.wikimedia.org/wikipedia/commons/1/14/Z800_2066_JKU.jpeg)
The zSeries family, introduced in 2000 with the z900, included IBM's newly designed 64-bit
z/Architecture
z/Architecture, initially and briefly called ESA Modal Extensions (ESAME), is IBM's 64-bit complex instruction set computer (CISC) instruction set architecture, implemented by its mainframe computers. IBM introduced its first z/Architecture-b ...
.
Processor units
The different processors on current IBM mainframes are:
* CP,
Central Processor
A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, ...
: general-purpose processor
* IFL,
Integrated Facility for Linux
The Integrated Facility for Linux (IFL) is an IBM mainframe and Power Systems processor dedicated to running the Linux operating system. On IBM Z and IBM LinuxONE machines, IFLs can be used with or without hypervisors such as z/VM and KVM. IFLs ...
: dedicated to
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 ...
OSes (optionally under
z/VM
z/VM is the current version in IBM's VM family of virtual machine operating systems. z/VM was first released in October 2000 and remains in active use and development . It is directly based on technology and concepts dating back to the 1960s, wi ...
)
* ICF, Integrated
Coupling Facility
In IBM System/390 and IBM Z mainframe computers, a Coupling Facility or CF is a piece of computer hardware or virtual machine that coordinates multiple processors.
A Parallel Sysplex
relies on one or more Coupling Facilities (CFs). A coupling f ...
: designed to support
Parallel Sysplex
In computing, a Parallel Sysplex is a cluster of IBM mainframes acting together as a single system image with z/OS. Used for disaster recovery, Parallel Sysplex combines data sharing and parallel computing to allow a cluster of up to 32 systems ...
operations
* SAP, System Assist Processor: designed to handle various system accounting, management, and
I/O channel operations
*
zAAP
The IBM System z Application Assist Processor (zAAP), previously known as the zSeries Application Assist Processor, is a mainframe processor introduced by IBM in 2004. zAAP engines are dedicated to running specific Java and XML workloads under z ...
, System z Application Assist Processor: currently limited to run only
Java
Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's List ...
and
XML
Extensible Markup Language (XML) is a markup language and file format for storing, transmitting, and reconstructing arbitrary data. It defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. T ...
processing
*
zIIP
In IBM System z9 and successor mainframes, the System z Integrated Information Processor (zIIP) is a special purpose processor. It was initially introduced to relieve the general mainframe central processors (CPs) of specific Db2 processing load ...
, System z Integrated Information Processor: dedicated to run specific workloads including
IBM Db2
Db2 is a family of data management products, including database servers, developed by IBM. It initially supported the relational model, but was extended to support object–relational features and non-relational structures like JSON a ...
,
XML
Extensible Markup Language (XML) is a markup language and file format for storing, transmitting, and reconstructing arbitrary data. It defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. T ...
, and
IPSec
In computing, Internet Protocol Security (IPsec) is a secure network protocol suite that authenticates and encrypts packets of data to provide secure encrypted communication between two computers over an Internet Protocol network. It is used in ...
Note that these are essentially identical, but distinguished for software cost control: all but CP are slightly restricted such they cannot be used to run arbitrary operating systems, and thus do not count in software licensing costs (which are typically based on the number of CPs).
There are other supporting processors typically installed inside mainframes such as
cryptographic
Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or '' -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adve ...
accelerators (
CryptoExpress), the
OSA-Express networking processor, and
FICON
FICON (Fibre Connection) is the IBM proprietary name for the ANSI ''FC-SB-3 Single-Byte Command Code Sets-3 Mapping Protocol'' for Fibre Channel (FC) protocol. It is a FC layer 4 protocol used to map both IBM's antecedent (either ESCON or para ...
Express disk I/O processors.
Software to allow users to run "traditional" workloads on zIIPs and zAAPs was briefly marketed by Neon Enterprise Software as "zPrime" but was withdrawn from the market in 2011 after a lawsuit by IBM.
Operating systems
The primary
operating system
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 in ...
s in use on current IBM mainframes include
z/OS
z/OS is a 64-bit operating system for IBM z/Architecture mainframes, introduced by IBM in October 2000. It derives from and is the successor to OS/390, which in turn was preceded by a string of MVS versions.Starting with the earliest:
* O ...
(which followed
MVS/ESA
Multiple Virtual Storage, more commonly called MVS, was the most commonly used operating system on the System/370 and System/390 IBM mainframe computers. IBM developed MVS, along with OS/VS1 and SVS, as a successor to OS/360. It is unrelated ...
and
OS/390
OS/390 is an IBM operating system for the System/390 IBM mainframe computers.
Overview
OS/390 was introduced in late 1995 in an effort to simplify the packaging and ordering for the key, entitled elements needed to complete a fully functional ...
in the
OS/360
OS/360, officially known as IBM System/360 Operating System, is a discontinued batch processing operating system developed by IBM for their then-new System/360 mainframe computer, announced in 1964; it was influenced by the earlier IBSYS/IBJOB ...
lineage),
z/VM
z/VM is the current version in IBM's VM family of virtual machine operating systems. z/VM was first released in October 2000 and remains in active use and development . It is directly based on technology and concepts dating back to the 1960s, wi ...
(which followed
VM/ESA
VM (often: VM/CMS) is a family of IBM virtual machine operating systems used on IBM mainframes System/370, System/390, zSeries, System z and compatible systems, including the Hercules emulator for personal computers.
The following versions ...
and VM/XA SP in the
CP-40
CP-40 was a research precursor to CP-67, which in turn was part of IBM's then-revolutionary CP 67CMS – a virtual machine/virtual memory time-sharing operating system for the IBM System/360 Model 67, and the parent of IBM's VM family. CP-40 ran ...
lineage),
z/VSE
VSEn (''Virtual Storage Extended'') is an operating system for IBM mainframe computers, the latest one in the DOS/360 lineage, which originated in 1965.
DOS/VSE was introduced in 1979 as a successor to DOS/VS; in turn, DOS/VSE was succeeded by ...
(which is in the
DOS/360 lineage),
z/TPF (a successor of Transaction Processing Facility in the
Airlines Control Program
IBM Airline Control Program, or ACP, is a discontinued operating system developed by IBM beginning about 1965. In contrast to previous airline transaction processing systems, the most notable aspect of ACP is that it was designed to run on most m ...
lineage), and
Linux on IBM Z
Linux on IBM Z or Linux on zSystems is the collective term for the Linux operating system compiled to run on IBM mainframes, especially IBM Z / IBM zSystems and IBM LinuxONE servers. Similar terms which imply the same meaning are ''Linux/390'', ...
(e.g.,
Debian
Debian (), also known as Debian GNU/Linux, is a Linux distribution composed of free and open-source software, developed by the community-supported Debian Project, which was established by Ian Murdock on August 16, 1993. The first version of D ...
,
Red Hat Enterprise Linux
Red Hat Enterprise Linux (RHEL) is a commercial open-source Linux distribution developed by Red Hat for the commercial market. Red Hat Enterprise Linux is released in server versions for x86-64, Power ISA, ARM64, and IBM Z and a desktop version ...
,
SUSE Linux Enterprise Server
SUSE Linux Enterprise (often abbreviated to SLE) is a Linux-based operating system developed by SUSE. It is available in two editions, suffixed with Server (SLES) for servers and mainframes, and Desktop (SLED) for workstations and desktop compu ...
). Some systems run
MUSIC/SP
''MUSIC/SP (Multi-User System for Interactive Computing/System Product''; originally "McGill University System for Interactive Computing") was developed at McGill University in the 1970s from an early IBM time-sharing system called RAX ( Remo ...
, as well as
UTS (Mainframe UNIX)
UTS is a discontinued implementation of the UNIX operating system for IBM mainframe (and compatible) computers. Amdahl created the first versions of UTS, and released it in May 1981, with UTS Global acquiring rights to the product in 2002. UTS Glo ...
. In October 2008, Sine Nomine Associates introduced
OpenSolaris on System z; it has since been discontinued.
Middleware
Current IBM mainframes run all the major enterprise
transaction processing
Transaction processing is information processing in computer science that is divided into individual, indivisible operations called ''transactions''. Each transaction must succeed or fail as a complete unit; it can never be only partially comple ...
environments and
database
In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases sp ...
s, including
CICS
IBM CICS (Customer Information Control System) is a family of mixed-language application servers that provide online transaction management and connectivity for applications on IBM mainframe systems under z/OS and z/VSE.
CICS family products ...
,
IMS,
WebSphere
IBM WebSphere refers to a brand of proprietary computer software products in the genre of enterprise software known as "application and integration middleware". These software products are used by end-users to create and integrate applications wi ...
Application Server,
IBM Db2
Db2 is a family of data management products, including database servers, developed by IBM. It initially supported the relational model, but was extended to support object–relational features and non-relational structures like JSON a ...
, and
Oracle
An oracle is a person or agency considered to provide wise and insightful counsel or prophetic predictions, most notably including precognition of the future, inspired by deities. As such, it is a form of divination.
Description
The word '' ...
. In many cases these
software
Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work.
At the lowest programming level, executable code consists ...
subsystems can run on more than one mainframe operating system.
Emulators
There are software-based emulators for the System/370, System/390, and System z hardware, including
FLEX-ES, which runs under
UnixWare or
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 ...
, and the freely available
Hercules
Hercules (, ) is the Roman equivalent of the Greek divine hero Heracles, son of Jupiter and the mortal Alcmena. In classical mythology, Hercules is famous for his strength and for his numerous far-ranging adventures.
The Romans adapted the Gr ...
, which runs under
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 ...
,
FreeBSD
FreeBSD is a free and open-source Unix-like operating system descended from the Berkeley Software Distribution (BSD), which was based on Research Unix. The first version of FreeBSD was released in 1993. In 2005, FreeBSD was the most popular ...
,
Solaris
Solaris may refer to:
Arts and entertainment Literature, television and film
* ''Solaris'' (novel), a 1961 science fiction novel by Stanisław Lem
** ''Solaris'' (1968 film), directed by Boris Nirenburg
** ''Solaris'' (1972 film), directed by ...
,
macOS
macOS (; previously OS X and originally Mac OS X) is a Unix operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac computers. Within the market of desktop and lapt ...
and
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 serv ...
.
IBM offers an emulator called zPDT (System z Personal Development Tool) which runs on Linux on
x86-64
x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit version of the x86 instruction set, first released in 1999. It introduced two new modes of operation, 64-bit mode and compatibility mode, along with a new 4-level paging mod ...
machines.
See also
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List of IBM products
The following is a partial list of products, services, and subsidiaries of International Business Machines (IBM) Corporation and its predecessor corporations, beginning in the 1890s.
This list is eclectic; it includes, for example, the ''AN/FS ...
*
Amdahl Corporation
Amdahl Corporation was an information technology company which specialized in IBM mainframe-compatible computer products, some of which were regarded as supercomputers competing with those from Cray Research. Founded in 1970 by Gene Amdahl, a for ...
*
IBM midrange computer
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IBM LinuxONE
Linux on IBM Z or Linux on zSystems is the collective term for the Linux operating system compiled to run on IBM mainframes, especially IBM Z / IBM zSystems and IBM LinuxONE servers. Similar terms which imply the same meaning are ''Linux/390'', ...
*
IBM Secure Service Container
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Input/Output Configuration Program
The Input/Output Configuration Program is a program on IBM mainframes.
History
In the original S/360 and S/370 architectures, each processor had its own set of I/O channels and addressed I/O devices with a 12-bit ''cuu'' address, containing a 4 ...
References
Further reading
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* Prasad, Nallur and Savit, Jeffrey (1994). ''IBM Mainframes: Architecture and Design'', 2nd ed. McGraw-Hill Osborne Media. .
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External links
Official IBM mainframe page (IBM Z)IBM Mainframe Resources & Forum
{{DEFAULTSORT:Ibm Mainframe
Computer-related introductions in 1952