My dates are approximate, which is why I said "1975 (I think)" instead of "1975". Your date of 1974 is equal to my "1975 (I think)". My date of 1974 for SVS is more accurate, because that is when I worked with it, and I began doing so very shortly after it was first available. VM was not called "VM" in 1967 any more than MVS was called "MVS" in the late 1960s, as the predecessor system to MVS was called MVT in the 1960s. VM's predecessor system was called "CP67". Both of these systems supported virtual storage and paging, but they had different names. SVS was not OS/VS1. SVS was "OS/VS2 Release 1." Try Google. I attended IBM sessions in SHARE during those years when IBM was announcing their future products, and I remember what they were and the hideous names IBM tried to use then (e.g., "OS/VS2 Release 2" rather than "MVS"). I also remember when IBM was announcing "VM", and it was not in 1967. It came out when all their other virtualized operating systems (OS/VS1, OS/VS2 Release 1, and OS/VS2 Release 2) were being released. OS/VS1 was a virtualization of OS/MFT. SVS, aka OS/VS2 Release 1, was a virtualization of MVT with only one 16 megabyte virtual address space. MVS, aka OS/VS2 Release 2, was also a virtualization of MVT but with multiple 16 megabyte address spaces. Bill Fairchild involved with IBM mainframe systems since February 1966
----- Original Message ----- From: "Ted MacNEIL" <[email protected]> To: [email protected] Sent: Monday, March 17, 2014 9:35:41 PM Subject: Re: Difference between MVS and z / OS systems I think your dates are wrong. VM was CP67 released in guess what year? MVS was first released in 1974. SVS was OS/VS1 and MVS was OS/VS2, IIRC. I'm sure, if I'm wrong, somebody'll correct me. - -teD - Original Message From: DASDBILL2 Sent: Monday, March 17, 2014 15:09 To: [email protected] Reply To: IBM Mainframe Discussion List Subject: Re: Difference between MVS and z / OS systems Close. OS/VS2 was released having been already pre-morphed into SVS and MVS. SVS was first called OS/VS2 Release 1, was first available in 1974, and that's when I worked with it. MVS was first called OS/VS2 Release 2, was first available slightly later (1975, I think), but I didn't begin working with MVS until 1977. VM was also first released around 1975. Other grand buzzwords that morphed were "loosely coupled multiprocessing" and "tightly coupled multiprocessing". The loose version became shared SPOOL, and the tight version became simply multiprocessing (several CPUs sharing the same central storage). And now we have SYSPLEXEs with both loosely and tightly coupled systems comPLEXly interwoven. Your date of 1980 for MVS is about the time when MVS's initially disappointing performance and RAS were greatly improved. Bill Fairchild ----- Original Message ----- From: "Gary Shiminsky" <[email protected]> To: [email protected] Sent: Monday, March 17, 2014 1:13:21 PM Subject: Re: Difference between MVS and z / OS systems Hi, If my memory serves me right, back in the 1970s there was OS/MFT, OS/MVT, OS/VS1, and OS/VS2. OS/VS2 morphed to OS/SVS and then OS/MVS(? Or maybe just MVS) starting in the 1980s. I worked on OS/VS1 Rel 7 back in the 79-80 time frame. I didn¹t get back to MVS till the mid 90¹s. Gary Gary L. Shiminsky Senior zVM/zVSE Systems Programmer Mainframe Technical Support Group Department of Information Technology State of New Hampshire 27 Hazen Drive Concord, NH 03301 603-271-1509 Fax 603-271-1516 Statement of Confidentiality: The contents of this message are confidential. Any unauthorized disclosure, reproduction, use or dissemination (either whole or in part) is prohibited. If you are not the intended recipient of this message, please notify the sender immediately and delete the message from your system. -----Original Message----- From: John Eells <[email protected]> Reply-To: IBM List <[email protected]> Date: Monday, March 17, 2014 at 1:51 PM To: IBM List <[email protected]> Subject: Re: Difference between MVS and z / OS systems >Helio Jose Da Silva wrote: >> Hello list, >> >> Someone can tell me the relevant differences between the MVS and z / OS >>systems? > >MVS was the prior name of what has become z/OS. What was started out as >MVS in 1974 was renamed to: > >MVS/SP Version 1 >MVS/XA Version 2 in 1981 >MVS/ESA Version 3 (1988), Version 4 (1991), and Version 5 (1994) >OS/390 (1996) >z/OS (2000) > >Along the way have come a plethora of new and enhanced functions. There >are more differences than there is time to list them. However, we still >call the "base control program" (BCP) "MVS" in many contexts, such as in >the names of various z/OS books, to differentiate it from the other >70-ish parts ("elements") of z/OS. > >-- >John Eells >z/OS Technical Marketing >IBM Poughkeepsie >[email protected] > >---------------------------------------------------------------------- >For IBM-MAIN subscribe / signoff / archive access instructions, >send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
