Mainframe, MVS and zOS Discussion

IBM S/360 mainframe (all of 8 MB RAM at 1 MHz)
Is not it an amazing picture?!

8 MB? More likely 8 KB of RAM. When I was in college, the S360 we used had 64 KB of RAM. When I started my first full-time IT job in 1977, the S370 we used only had 3 MB of RAM.

I could not think between 8 MB and 8 KB - was rather confused if the girl is/was in night or day shift!?

Jokes apart, this is from wiki. 8 MB was not the usual but existed:

The slowest System/360 models announced in 1964 ranged in speed from 0.0018 to 0.034 MIPS; the fastest models were approximately 50 times as fast with 8 KB and up to 8 MB of internal main memory, though the latter was unusual, and up to 8 megabytes of slower Large Capacity Storage (LCS). A large system might have as little as 256 KB of main storage, but 512 KB, 768 KB or 1024 KB was more common.

The picture shows an early System/360 Model 30 which could have up to 64KB of main (core) storage, and could not attach any LCS. Note that the "Logo Bar" on top of the console is black at the left end (where it says 'IBM') and is white for the rest of the bar (where you can barely make out the words 'SYSTEM 360'). This is how the System/360 prototypes looked - but most, if not all, System/360s shipped with an all black Logo Bar and the word 'SYSTEM" was changed to 'System'.

In 1967-1972 the IBM Boston Programming Center had a System/360 Model 50 with 256KB of main storage and 8MB of LCS. It was used to develop time sharing systems (CPS and CS/I) that dedicated real memory to each terminal user, before the availability of virtual memory. In those days very few computers were installed with more than 1MB of memory.

mainframe360 wrote:In those days very few computers were installed with more than 1MB of memory.

This reminds me about another picture here: viewtopic.php?f=36&t=845