mainframe
34 ResultsDictionary
mainframe
A state-of-the-art computer for mission critical tasks. Today, mainframe refers to a class of ultra-reliable servers from IBM that is designed for enterprise-class and carrier-class operations....
Dictionary
Definition: mainframe
A state-of-the-art computer for mission critical tasks. Today, mainframe refers to a class of ultra-reliable servers from IBM that is designed for enterprise-class and carrier-class operations.
However, in the "ancient" mid-1960s, all computers were mainframes, since the term referred to the "main" CPU cabinet. The first mainframe vendors were (alphabetically) Burroughs, Control Data, GE, Honeywell, IBM, NCR, RCA and Univac, otherwise known as "IBM and the Seven Dwarfs." After GE and RCA's computer divisions were absorbed by Honeywell and Univac respectively, the mainframers were known as "IBM and the BUNCH."
IBM Is the Mainframe Vendor
For decades, IBM was the dominant vendor in the mainframe business. Although many tried to compete by offering compatible machines, they no longer do (see IBM-compatible mainframe). HP, Unisys, Sun and others make machines that compete with IBM mainframes in many industries but are mostly referred to as servers. In addition, non-IBM mainframe datacenters have hundreds and thousands of servers, whereas IBM mainframe datacenters have only a few machines.
There Is a Difference
One might wonder why mainframes cost hundreds of thousands of dollars when the raw gigahertz (GHz) rating of their CPUs may be only twice that of a PC costing 1,000 times less. Here's why:
Lots of Processors, Memory and Channels
Mainframes support symmetric multiprocessing (SMP) with several dozen central processors (CPU chips) in one system. They are highly scalable. CPUs can be added to a system, and systems can be added in clusters. Built with multiple ports into high-speed caches and main memory, a mainframe can address thousands of gigabytes of RAM. They connect to high-speed disk subsystems that can hold petabytes of data.
Enormous Throughput
A mainframe provides exceptional throughput by offloading its input/output processing to a peripheral channel, which is a computer itself. Mainframes can support hundreds of channels, and additional processors may act as I/O traffic cops that handle exceptions (channel busy, channel failure, etc.).
All these subsystems handle the transaction overhead, freeing the CPU to do real "data processing" such as computing balances in customer records and subtracting amounts from inventories, the purpose of the computer in the first place.
Super Reliable
Mainframe operating systems are generally rock solid because a lot of circuitry is designed to detect and correct errors. Every subsystem may be continuously monitored for potential failure, in some cases even triggering a list of parts to be replaced at the next scheduled maintenance. As a result, mainframes are incredibly reliable with mean time between failure (MTBF) up to 20 years!
Here to Stay
Once upon a time, mainframes meant "complicated" and required the most programming and operations expertise. Today, networks of desktop clients and servers are just as complex, if not more so. Large enterprises have their hands full supporting thousands of PCs along with Windows, Unix and Linux and possibly some Macs for good measure.
With trillions of dollars worth of IBM mainframe applications in place, mainframes may hang around for quite a while. Some even predict they are the wave of the future!
Mainframe System
UNIVAC Mainframe
Mainframes provided the computing power for major corporations for more than 50 years. Sperry Rand (Univac), IBM, GE, RCA, NCR, Burroughs, Honeywell and Control Data were the first companies to make mainframes in the U.S. This picture was taken in the mid-1970s. (Image courtesy of Unisys Corporation.)
THIS DEFINITION IS FOR PERSONAL USE ONLY
All other reproduction is strictly prohibited without permission from the publisher.
© 1981-2010 The Computer Language Company Inc. All rights reserved.
Sponsored White Papers, Webcasts & Resources
-
Improve the Performance of SAN Storage
Check out this white paper to learn how to improve and maintain the performance of your SAN by adding defragmentation tools into your computing. Keep reading to learn more.
-
Mainframe Ubuntu Linux?
Sources close to Canonical and IBM are telling me that Ubuntu may soon be certified on IBM's System p mini-computers and blades and System z mainframes.
-
Intel previews next Itanium mainframe chip
Intel will preview its next Itanium processor and improvements include better power management, reliability and architecture. No timeline was set for the next Itanium, code-named Poulson.
-
Three Reasons Why Apple-Unisys Is a Smart Partnership
Apple and Unisys may seem like a baffling partnership for bringing the iPad and iPhone to the enterprise and government markets. But Unisys does bring a number of important things to this marriage.
-
IBM ups 2010 outlook; New mainframes spur hardware sales
IBM upped its 2010 earnings outlook after delivering a strong third quarter. The company showed strength in businesses ranging from mainframes to middleware to analytics.
-
Microsoft reinvents the mainframe
At its Tech-Ed conference today, Microsoft took the wraps off a set of new features that will be included in Service Pack 1 for Windows Server 2008 R2 and Windows 7. Wth RemoteFX, the goal is to...
-
-
Dissecting BMC and CA Technologies' cloud efforts
BMC Software and CA Technologies have a lot in common including efforts to target large enterprises with a promise to help CIOs better manage hybrid cloud data centers. Do they pass the cloud...
-
IBM accused of mainframe monopoly
A small US company has filed a complaint with the European Commission, accusing IBM of abusing its position in the European mainframe market.
-
From Chapter one: Data Processing and the IBM Mainframe
What the CoBIT framework does is establish minimal guidelines for data center operational documentation -as distinct from the actual operation.
-
From Chapter one: Data Processing and the IBM Mainframe
The thing that's most striking about the "heavy lifting" carried out by the typical zSeries based data center in 2006? There have been changes in execution, but not in role or overall management...
-
From Chapter one: Data Processing and the IBM Mainframe
The controls that developed around the 360 environment were all predicated on the primary concerns expressed by Finance management: that nothing interrupt processing critical to Finance. Thus...
-
From Chapter one: Data Processing and the IBM Mainframe
COBOL reflects 1920s data processing methods - and because the IBM 360 implemented COBOL it became the foundation for an entire worldview - a culture founded entirely on a refusal to adapt to...
-
From Chapter one: Data Processing and the IBM Mainframe
The nature of data processing is to be long winded, boring, and dominated by acronyms derived from long gone technologies and business practices.
-
BIt: From Chapter one: Data Processing and the IBM Mainframe
COBOL reflects 1920s ways of thinking about data processing - and has critically influenced multiple generations of data processing thinkers since. T
-
Questioning IT
A good Windows CIO asked about systems integrity will simply tell you that PC security is a losing game - he'll talk about the necessity of keeping up with industry norms: about routinized...
-
The PC vision was lost from the get-go
A guest blog - by Mark Miller - quoting Alan Kay "The computer revolution hasn't happened yet."
-
Survey: SOA and the 'second life' of mainframes
Thanks to Web services and SOA, we're all mainframe users these days.
-
ROI Lost: IBM Puts the Screws on a Loyal Customer
If you ever thought that the contents of the contract you sign with your IT vendor isn’t the most important part of your technology strategy, read on. And if you ever thought that your vendor...
-
Managing a greener storage environment
Growth in storage capacity is outpacing the improvement in storage technology, resulting in a steady increase in worldwide power consumption. IBM System Storage CTO Clod Barrera tells how to stay...
-
Xsigo Network and I/O Virtualization
I had a chance to speak with an interesting newcomer to the world of virtualization, Xsigo. Jon Toor, Xsigo's VP of Marketing, and I chatted about Xsigno's VP780 Network Director. I came away...
-
The cost of mainframe Linux
The data center never get close to break even on capital cost and the organization as a whole will incur significant losses because users expect better and will adapt - usually by buying wintel...
The best of ZDNet, delivered
ZDNet Newsletters
Get the best of ZDNet delivered straight to your inbox
Vendor Showcase
Facebook Activity
