🚀 go-pugleaf

Anne & Lynn Wheeler <ly...@garlic.com> writes:
> which morphs into cp67/cms when standard 360/67 with virtual memory
> becomes available 
> https://en.wikipedia.org/wiki/CP/CMS
>
> above history somewhat garbled. There was CP67 "L" floor production
> system at Cambridge (and I distributed/supported for othere internal
> datacenters). There were the "H" updates to CP67 "L" ... which provided
> optional 370 virtual machines (new instructions and slightly different
> format for virtual memory tables). And there was the "I" udpates to CP67
> "H", which was CP67 modified to run in a 370 machine instead of 360/67
> machine. CP67I was regularly running production in CP67H virtual
> machines a year before the first 370 engineering machine with virtual
> memory support was available. CP67I with San Jose updates to support
> 3330 disks & 2305 fixed-head drum (CP67SJ) ran production on large
> number of internal 370s ... well before VM370 was available.

re:
http://www.garlic.com/~lynn/2018e.html#45 DEC introduces PDP-6 [was Re: IBM introduces System/360]

I've heard it in the past as folklore ... but don't believe I've ever
met somebody that actually did such a thing. Standard procedure wouldn't
give regular users privileged permissions to production machine.  Even
developers wouldn't have their working user with privileged command
permissions to first level machine (it would be poor policy to have
regular user with permissions, sort of like giving every user root
permissions in unix).

Sysadmin sank IBM mainframe by going one VM too deep; Tried to blame it
on a bug, but logs don't lie
http://www.theregister.co.uk/2018/07/23/sysadmin_sank_ibm_mainframe_by_going_one_vm_too_deep/

-- 
virtualization experience starting Jan1968, online at home since Mar1970