From: ldo@nz.invalid   
      
   On Wed, 17 Sep 2025 00:25:32 +0100, David Wade wrote:   
      
   > Its interesting you say "modern virtualisation" because most of the   
   > various "tweaks and tricks" modern X64 virtualisations use were   
   > developed by IBM in the 1970s an 80s for VM/XA & VM/ESA. X86 and AMD   
   > CPUs didn't get these until 2005/6. zVM is really slick... but   
   > expensive.   
      
   IBM invented virtualization, in the beginning to run multiple instances of   
   CMS. This was their attempt to compete with interactive timesharing   
   systems from DEC and other vendors. Trouble is, unlike those others, which   
   had multiuser support built-in, CMS was single-user only. So as a quick   
   hack, the “CP” (later “VM”) hypervisor was introduced. Each user   
   effectively had their own (virtual) machine. Sounds like a neat idea,   
   until you realize that communication and sharing of info between machines   
   (i.e. between different users) wouldn’t have been so easy.   
      
   Did IBM ever address that problem of communication between machines?   
      
      
      
   > Are new installations of VMS still being sold?   
      
   Probably not.   
      
   > So you can buy Solaris and I think HP-UX ...   
      
   And of course macOS, but that’s not in the server/enterprise league. But   
   it still likely, far and away, the most popular OS that can legally call   
   itself “Unix”.   
      
   (Not that many people care about that any more.)   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)