On 7 April 1964 IBM announced the System/360, which is now recognized as the first IBM Mainframe computer system. IBM Board Chairman Thomas J. Watson Jr. called the event the most important product announcement in the company’s history. At a press conference at the IBM Poughkeepsie facilities, Mr. Watson said:
“System/360 represents a sharp departure from concepts of the past in designing and building computers. It is the product of an international effort in IBM’s laboratories and plants and is the first time IBM has redesigned the basic internal architecture of its computers in a decade. The result will be more computer productivity at lower cost than ever before. This is the beginning of a new generation, not only of computers, but of their application in business, science and government.”
More than 100,000 businessmen in 165 American cities today attended meetings at which System/360 was announced. 50 years later, I wonder whether there are 100,000 people that work with the IBM Mainframe in The USA and maybe globally…
During this 50 year evolution, the IBM Mainframe has seen opinion polarize, sometimes from the same person:
- In March 1991, Stewart Alsop stated “I predict that the last mainframe will be unplugged on March 15, 1996.”
- In February 2002, Stewart Alsop stated “It’s clear that corporate customers still like to have centrally controlled, very predictable, reliable computing systems, exactly the kind of systems that IBM specializes in.”
Obviously the IBM Mainframe server is still here and just like in 1964, in the early 1990’s it did evolve into just another server on the distributed network and the use of routers, incorporating POSIX compliance and so on…
As we all know, the IBM Mainframe has always evolved, continues to evolve and in theory, and often in real-life, can run any workload.
Let’s reprise some of the notable IBM Mainframe models and associated functions since April 1964:
| Family Name | Announced | Notable Function Introduction |
| S/360 | April 1964 | 24-bit addressing (32-bit architecture) |
| S/360 | August 1965 | Virtual storage |
| S/360 | January 1968 | High speed cache |
| S/370 | June 1970 | Disk & printer support |
| S/370 | August 1972 | Virtual storage & multi-processor support |
| S/370 XA | June 1983 | Extended storage 24-bit/31-bit addressing |
| S/390 ESA | September 1990 | ESA & OS/390 operating systems |
| zSeries (zArchitecture) | October 2000 | z operating systems, 24/31/64-bit addressing supported concurrently |
| zSeries z9 EC | July 2005 | zIIP specialty engine |
| zSeries z10 EC | February 2008 | High capacity/performance (quad core CPU chip) |
| z196 (zEnterprise) | July 2010 | 96-way core design & distributed systems integration (zBX) |
| zEC12 | August 2012 | Integrated platform for cloud computing, integrated OLTP & data warehousing |
It’s interesting to note that the purchase price of an IBM mainframe is about the same, comparing 1964 to 2014, let’s say~$100,000. Of course, you can’t compare the feeds and speeds of these machines, they’re exponentially different. However, just as the S/360 in 1964 played a pivotal part in shaping data processing for that decade, subsequent evolutions of the IBM Mainframe follow in that tradition, lowering the cost of IT and simplifying business management.
I’m sure a lot of us have enjoyed our time working with the IBM Mainframe server and long may that be the case, for future generations of IT professionals.