Big Iron Birthday: Mainframes Are 50

IBM

IBM announced the System/360 mainframe in April 1964, kicking off a revolution in centralised computing

Exactly 50 years ago, IBM announced its first true mainframe. It all began with the humble System/360, which enabled large businesses to integrate all of their data processing applications into a single management system for the very first time.

System/360 increased central memory capacity from 8,000 to 524,000 characters (roughly 500k) and introduced modular design, which meant customers were able to purchase a smaller system, safe in the knowledge they could always upgrade if their needs grew, without having to rewrite software.

This remains true today – software written for System/360 still maintains application-level compatibility with the latest IBM System z servers. The classic mainframe is considered by many to be one of the most successful computers in history, influencing the design and architecture of digital devices for years to come.

COBOL, the programming language which is mainly used to work with mainframes, celebrated its 50th birthday in 2009.

Golden anniversary

zEnterprise System 3The first general purpose automatic digital computer built by IBM dates back to 1944. However, it was the System/360 that put mainframes on the map.

IBM originally announced a series of six System/360 computers and 40 common peripherals. The company eventually delivered fourteen models, including rare customised units for NASA which enabled the Apollo space programme.

The death of the mainframe has been predicted for at least two decades, and yet these huge machines stay surprisingly relevant, especially in financial, healthcare, transport and insurance industries.

According to stats provided by Micro Focus, 96 of the world’s top 100 banks and 90 percent of the world’s largest insurance companies rely on mainframes – many of which have had no downtime for more than a decade.

IBM adds that Internet users post 6,900 tweets and make 60,000 Google searches every second – an impressive number, but it pales in comparison with 1.1 million transactions that mainframes around the world process in the same amount of time.

We can’t talk about mainframes without mentioning COBOL – one of the oldest programming languages, foundations for which were laid by the legendary computer scientist Grace Hopper herself. Today, COBOL is experiencing something of a crisis – after more than 50 years in use, it is rarely taught at universities, and the current generation of software developers seems to have little interest in its accurate business logic and ability to do very precise numeric calculations.

And yet, research suggests an average person interacts with a COBOL application at least ten times a day, and the workload on existing mainframes is actually increasing despite the proliferation of distributed computing models. This results in huge demand for COBOL specialists.

“The age of the mainframe is starting to work against it. Pressured by growing demands for innovation, CIOs are obliged to look at all options. After all, IT backlogs continue to increase. Yet, the enduring, profound value of the applications and the peerless capabilities of the mainframe make any replacement strategy very high risk,” told us Derek Britton, director at Micro Focus.

Below, you can see some of the key IBM mainframe models throughout the years:

IBM Mainframe Computers

Image 3 of 14

System/370
The control panel

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