4 ms·

Persnickety but also curious comment: wasn't the System/360 the first mainframe?

by chx 4y ago

rst 4y ago
By the time the S/360 was announced, IBM had already been producing top-of-the-line systems with the main processor sharing memory with several I/O "channels" for several years -- which would be "mainframes" by any reasonable definition I can think of other than "S/360 and derivatives" (which, by the way, excludes competing mainframe systems from Univac and Burroughs, among others).
KerrAvon 4y ago
The UNIVAC, in 1951, was probably the first mainframe recognizable as such. Big boxes, tape drives, lots of I/O. For a brief time, "Univac" was synonymous with "computer". IBM quickly put a stop to that, of course. https://en.wikipedia.org/wiki/UNIVAC https://en.wikipedia.org/wiki/UNIVAC
- cwillu 4y ago
  Hence Asimov's “The Last Question” referring to the computer as Multivac and variations thereof, culminating in “Universal AC”.
msla 4y ago
As others have said, the System/360 line wasn't even IBM's first generation of mainframes, but it was the first line of computers with an ISA as we understand the term: A document describing an environment for software to be written for independent of any specific machine, such that the machines would be implementations of that ISA and multiple different machines could all run the same software. IBM used this to make a whole line of different mainframes at different price points that could all run (mostly) the same software, to the limits of different machines having different amounts of RAM and some machines not having disk drives and some opcodes not being implemented on certain low-end models, just like how it works these days. But that came about in the mid 1960s, and IBM had been making commercial mainframes for over a decade by then.
epc 4y ago
System/360 was the attempt by IBM to unify its existing computing systems (1401, 700 series, 7030, 1620, etc). All were "mainframes" by our current definition.

Persnickety but also curious comment: wasn't the System/360 the first mainframe?

by chx 4y ago

Persnickety but also curious comment: wasn't the System/360 the first mainframe?

rst 4y ago

By the time the S/360 was announced, IBM had already been producing top-of-the-line systems with the main processor sharing memory with several I/O "channels" for several years -- which would be "mainframes" by any reasonable definition I can think of other than "S/360 and derivatives" (which, by the way, excludes competing mainframe systems from Univac and Burroughs, among others).

KerrAvon 4y ago

The UNIVAC, in 1951, was probably the first mainframe recognizable as such. Big boxes, tape drives, lots of I/O. For a brief time, "Univac" was synonymous with "computer". IBM quickly put a stop to that, of course. https://en.wikipedia.org/wiki/UNIVAC https://en.wikipedia.org/wiki/UNIVAC

cwillu 4y ago
Hence Asimov's “The Last Question” referring to the computer as Multivac and variations thereof, culminating in “Universal AC”.

msla 4y ago

As others have said, the System/360 line wasn't even IBM's first generation of mainframes, but it was the first line of computers with an ISA as we understand the term: A document describing an environment for software to be written for independent of any specific machine, such that the machines would be implementations of that ISA and multiple different machines could all run the same software. IBM used this to make a whole line of different mainframes at different price points that could all run (mostly) the same software, to the limits of different machines having different amounts of RAM and some machines not having disk drives and some opcodes not being implemented on certain low-end models, just like how it works these days. But that came about in the mid 1960s, and IBM had been making commercial mainframes for over a decade by then.

epc 4y ago

System/360 was the attempt by IBM to unify its existing computing systems (1401, 700 series, 7030, 1620, etc). All were "mainframes" by our current definition.