Announced November 12, 1980 and withdrawn August 4, 1987.
The following is the text of an undated IBM marketing brochure probably published in 1982.
The IBM 3081 Processor Complex is a cost-effective growth solution for users who require the power and performance of a large data processing system. Three versions of the 3081, Model Groups D, G and K, offer excellent processing power and capacity and attractive physical characteristics. For users of either Model D, G or K, the introduction of the System/370 Extended Architecture mode of operation provides an option which adds functional enhancements, while permitting continued execution of existing programs. With these enhancements, the 3081 Processor Complex offers the power and growth potential to meet today's data processing requirements, as well as those of the future.
- The IBM 3081 Processor Complex offers flexible growth steps in the 308X family of processors, between the 3083 Model Groups F, B and J and the 3084.
- The dyadic concept offers "under the cover" dual processors which should improve system availability compared to a uniprocessor. The packaging technology used is the result of several years of systematic research. Benefits of this technology include enhanced reliability, improved availability and serviceability.
- There are three Model Groups: D, G and K. They are all compatible with other 30XX processors to protect programming investments and to allow for orderly transition as you step up in processing power.
Model D is capable of an instruction execution rate of up to 21 times that of a 3033UP running under MVS/SP with identical programs and similar configurations.
Model G, the newest of the 3081 Model Groups, offers a slightly greater internal execution rate than the Model D.
Model K is capable of an instruction execution rate ranging from 1.3 to 1.4 times that of the 3081 Model D.
As throughput measurements are highly dependent on configuration, applications and operating characteristics, individual jobstreams should be carefully evaluated before any estimate of throughput rate can be made.
The Models D, G and K offer the option of operating with either System/370 architecture or the new System/370 Extended Architecture.
IBM 3081 support of System/370 architecture incorporates the System/370 Universal Instruction Set, System/370 Extended Facility, 3033 Extension feature, Extended Addressing, Virtual Machine Assist, Preferred Machine Assist, and Data Streaming as standard features.
These provide the hardware and microcode support for a number of important extensions introduced into the System/370 product line in the past few years:
- Paging. Reduced execution time for paging operations.
- Real Storage Management: Reduced execution time for several high-frequency Real Storage Management functions.
- I/O Processing: Offloading of some of the I/O processing to the channels.
- Cross Memory Services: Optimizes performance for this extended function
System/370 Extended Architecture provides further extensions designed to support the very large application systems you'll be developing in the '80s. These include:
- Coexistence with System/370 architecture through bimodal execution of program modules.
- Virtual and real storage addressability to two gigabytes.
- Dynamic Channel Subsystem.
- Dyadic processor design consisting of two integrated central processors, each with access to channels and central storage.
- 16 or 24 integrated channels, all with data streaming.
- 16, 24 or 32 megabytes of storage.
- Support for up to 4,080 I/O devices.
- Extensive use of microcode and advanced new technology for processor unit logic.
- A dedicated service support console for concurrent interaction with diagnostic and support functions.
- Significant reductions in power, space and cooling requirements.
Field upgradability is available to the 3081 Model Group G from the 3083 Model Group B; to the 3081 Model Group K from the 3083 Model Group J, or from the Model Groups D or G; and to the 3084 from the Model Group K.
The IBM 3082 is the interface for controlling and servicing the entire 3081 Processor Complex. To supervise the 3081 operation, it performs unit initialization, and make the various elements available for use by the 3081 Processor Unit. The 3082 distributes microcode loads, provides control unit function for the system console and assists in hardware error recovery.
For system maintenance and diagnosis, it controls an integrated service support console, provides communication support to remote locations, monitors, logs and analyzes failures and identifies failing components to allow for rapid intervention and repair. Error data collected and diagnostic programs are stored on an integrated disk file.
Where a telecommunications link does not exist, error log information can be physically transferred for analysis via a system diskette. The service support console can also be used as a backup to a malfunctioning system or operator console. An optional IBM printer can be attached to print hard-copy snapshots of data displayed on the service support or system console.
The IBM 3089 is an optional unit which is connected to your mainline supply. It is designed to provide a stabilized 400 Hertz AC power source to units of the 3081 Processor Complex. Its low noise level should allow it to be installed in your data processing center.
The IBM 3087 incorporates heat exchangers, controls and two water pumps to supply cooling water in a closed loop to the IBM 3081 Processor Unit.
The temperature and flow rate of the cooling water supplied to the 3081 is continuously monitored by the microcode-driven 3082 Processor Controller. Any deviation from acceptable limits is signaled to the system operator.
The 3082 also periodically switches between the two coolant water pumps to help insure high system availability.
System functions are provided by a tabletop IBM 3278 Display Console Model 2A. It connects directly to the 3082 Processor Controller.
Operator console facilities can be provided by normal end-user terminals, such as the proven IBM 3277 and 3278 Display Stations and the IBM 3279 Color Display Station. They connect to the 3081 Processor Unit via IBM 3274 Control Units.
The system operator consoles have a remote operation capability far in excess of previously available consoles, allowing a better opportunity to construct a master control center appropriate to your particular site layout. In addition, an optional accessory table with space for two displays is available. It is designed to provide out-of-sight cable routing for displays and phones, and it incorporates a bulletin-board-like end partition for posting new procedures, messages, schedules and charts.
The 3081 Processor Complex can be operated with either MVS/SP, MVS/XA or VM/SP.
- MVS/System Product (MVS/SP) supports all models of the 3081. Version 1 incorporates the support for the processor as well as the architectural extensions for the System/370 mode of operation.
- MVS/Extended Architecture (MVS/XA) is comprised of MVS/SP Version 2 and a new program product called the Data Facility Product. It provides the base support for System/370 Extended Architecture. MVS/XA also provides external compatibility with existing MVS systems at different levels, i.e., MVS/370 catalogs, JCL and user data set formats, most existing problem-state programs at source and object code level, and most operator messages and commands.
- VM/System Product (VM/SP), with the VM/SP High Performance Option, supports the 3081 models in System/370 mode. It offers enhancements to large-system VM users with the new VM/SP High Performance Option. These include:
||3081 Segment Protection: Improves 3081 VM/CMS performance.
||Preferred Machine Assist: Reduces VM overhead when running an MVS/SP Release 1.3 guest virtual machine.
||Support for more than 16 megabytes of real storage.
||Support for the IBM 3880 Storage Control Model 11 and 3350 Paging Subsystem.