From: jeffsavit <email@example.com>
Date: October 19, 2010 11:26:59 AM EDT
Subject: [hercules-390] Current status of MTS ?
Nostalgic war stories are a much more fun topic, IMO, so...
From: Mike Alexander <firstname.lastname@example.org>
Date: October 19, 2010 12:32:01 PM EDT
I'm curious which LISP interpreter that was. I'm sure it wasn't
From: rhtatum <email@example.com>
Date: October 19, 2010 2:45:07 PM EDT
As a matter of historical interest, when was MTS doing these things (different storage keys for monitor, user code, data)? Mike wrote something called the elpar Moniter/OS circa 1970 that did just that - if you tried to write and execute self-modifying code or scribble o9n the monitor, you got got kicked off the machine immediately with a memory protect violation. About reentrant code - that's simple enough; why are folks so afraid of writing recursive routines? The old example of writing factorial n (N!) iteratively or recursively turns out to show just how badly IBM did things in PL/1 when one wanted to do recursion. I implemented Ackerman's function as an exercise just to see how simply things could be done. id a getmain for an unreakl amount of memory, used that for a stack. The computation part was 18 instructions, 48 (decimal) bytes; tried it on a 360/65 in IBM's South Road aba with a 3 minute run-time limit. Got the thing back with an indicated time of 8 minutes and desperate indications of the operators trying to stop the fool thing after big oz got its knickers in a knot. I've forgotten how far it got on A(5,5), somewhere on 3,5); did a little induction on what was the simplest purely recursive function known at the time (1968), saw that writing A(5,5) would have taken many, many reels of 2400ft/1600bpi tapes written as gapless stuff. Learned then to consider the consequences of supposedly bright ideas ...
From: Mike Alexander <firstname.lastname@example.org>
Date: October 19, 2010 5:47:09 PM EDT
--On October 19, 2010 1:45:07 PM -0500 <email@example.com>
From: Robert Hodge <firstname.lastname@example.org>
Date: October 19, 2010 7:40:34 PM EDT
With all this talk about MTS, is there any way someone could get a copy of MTS
From: rhtatum <email@example.com>
Date: October 19, 2010 10:33:40 PM EDT
No, MTS probably won't run under Hercules - I looked up MTS using a google search, and it seems that there was an additional operation code that the folks that created MTS either did themselves or had IBM implement for switching between pieces of MTS, user programs, etc. Someone would have to write the simulation code for that op-code for MTS to run under Hercules-390. Other than that, machine operation codes are machine operation codes, and if a program/operating system/whatever runs on the "real iron", it will run under Hercules.
From: Mike Alexander <firstname.lastname@example.org>
Date: October 19, 2010 10:50:44 PM EDT
--On October 19, 2010 9:33:40 PM -0500 rhtatum <email@example.com>
From: rhtatum <firstname.lastname@example.org>
Date: October 19, 2010 11:14:20 PM EDT
No URL pops into my mind, I just did a Google search for MTS and found it - according to the thing I found, there was a shortcoming for such systems as TSS and MTS, an instruction was added and the resulting S/360 with the additional op-code became the S/360 Model 67 (and a bunch of other stuff happened) and the capability gained was incorporated in S/370, so naturally one would find that X has it.
From: Mike Schwab <Mike.A.Schwab@gmail.com>
Date: October 20, 2010 1:56:48 AM EDT
Probably virtual storage (loading the translations tables)? Wasn't on
From: Dave <email@example.com>
Date: October 20, 2010 2:48:43 AM EDT
MTS has used Virtual Memory since the start and therefore originally in only
From: Peter <firstname.lastname@example.org>
Date: October 20, 2010 8:28:35 AM EDT
How about a foundation whose aim is to educate people about MTS?
From: Gavin Eadie <email@example.com>
Date: October 20, 2010 8:39:21 AM EDT
On Oct 20, 2010, at 2:48 AM, Dave wrote:
. . . If you are interested, there is an account of what UBC went through back in 1968 when they became the first site after Michigan to install MTS. See: http://archive.michigan-terminal-system.org/discussions/how-did-sites-learn-about-and-make-the-decision-to-use-mts/2ubc. . . .
On Jan 8, 2012, at 8:12 PM, Tom Jacobsen wrote:
Reading this made me curious about the history of events behind the decision to release MTS to the Hercules community. Most organizations these days are not very interested in releasing their intellectual property in this way. It would be interesting to hear the story of the person(s) who convinced upper administration to allow for this to be released. (whoever it was, thank you!). Perhaps this story can be added to the discussion section of the archive site where the UBC article is.
From: Jeff Ogden
Subject: Re: [H390-MTS] I am missing something [or an account of how MTS became publicly available, posted to the H390-MTS e-mail group]
Date: January 25, 2012 5:08:28 PM EST
I'm not sure how much of a story there is to tell. It took a bit of time, but making MTS available was remarkably uncontroversial.
The University of Michigan stopped offering its MTS service to end users at the end of June 1996. Some of the other MTS sites had stopped earlier and some later. RPI was the last and stopped in 1999, but had been phasing MTS out for several years prior to that. See:
* RPI MTS Termination memo, June 1998 at http://archive.michigan-terminal-system.org/documentation/documents/MTSShutdownAtRPI-June1998.pdf
* "Dropping the Mainframe Without Crushing the Users: Mainframe to Distributed UNIX in Nine Months", Paper presented at LISA VI: 6th Large Installation Systems Administration Conference, Long Beach, California, USA, October 1992 at http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.56.2631&rep=rep1&type=pdf
MTS continued to run occasionally on the IBM mainframe at U-M for internal use for a time, about a year I think, but that was over by mid-year 1997. Some U-M units ran MTS on emulators such as FLEX-ES and possibly others, mostly to get access to archived materials on magnetic tape. This use was pretty informal from the start and became more informal as time passed. Mike Alexander was instrumental in taking steps to preserve the MTS distribution tapes and Tom Valerio did much/most/all of the work to preserve the 1996 version of the system and to get it running on emulators. Steve Burling was involved in some of this too, but I'm not clear on exactly who did what or when.
I'm not sure who was the first to run MTS under Hercules. Probably Mike or Tom. I know I got a copy to run from Gavin Eadie early in 2005. Most everyone still had day jobs at this point.
I noticed that there was quite a lot of information about MTS available online, but that the information was incomplete and some of it was at least slightly wrong. The MTS Wikipedia article in 2009 included this plea toward the end of the article:
This operating system-related article is a stub. You can help Wikipedia by expanding it.
So I started to update the MTS article, which lead to writing a couple of new and updating other Wikipedia articles. I was asking Mike, Tom, and others for help remembering what was done when. I ended up renewing contact with folks from several other MTS sites in the U.S., Canada, and the UK that I hadn't been in touch with for 15 or 20 years, which was fun.
As time passed some of us retired.
I was coming across more and more material that for one reason or another wasn't appropriate for Wikipedia. And so in the fall of 2010 after consulting with Mike and Gavin, I registered the domain name, created the MTS Archive web site at archive.michigan-terminal-system.org, and began using the site as a place to gather this information. The hope/plan was and remains to find other more institutional homes for the materials so they are more likely to have a longer term future than an individual or group of individuals can guarantee.
In June 2010 Mike, Tom, Gavin, and I got in contact with the staff of the University of Michigan's Bentley Historical Library here in Ann Arbor. The Bentley already had on deposit materials related to computing and connectivity including materials on MTS that they had received from many sources (from Aaron Finerman the 2nd Director of U-M's academic Computing Center, Bernie Galler a professor of Computer Science and a long time Associate Director at the CC, Mike Alexander, and many others). Pretty much all of this material consisted of physical objects stored in bankers boxes on shelves in the stacks at the Bentley. Very little or none of it was online. When we met with the folks at the Bentley we were interested in making more MTS materials available and, if possible, at least some of them online. The Bentley staff were very receptive and offered to make the materials available via the U-M's Deep Blue digital archive. Mike converted many of the MTS manuals into the PDF/A format that archivists like and this and other material was given to the Bentley on DVDs.
We also worked with Al at Bitsavers.org. Bitsavers already had some materials related to MTS, but in January 2011 Al was kind enough to accept many more PDF documents. And by March 2011 the Bentley had deposited the PDFs in Deep Blue.
I also worked with the staff at the U-M Library to have over 250 MTS related documents that had been scanned by Google and were available in the Hathi Trust Digital Library switched from "limited search only" to "full view" access. The Associate Director of the Library was kind enough to authorize me to request the switch for materials that had been produced by the U-M's Computing Center, where I had been Senior Associate Director.
Over the years there had been talk of and speculation about what it would take to make a run-able version of MTS more widely available. Some of those discussions were private, but some took place on the Hercules-390 e-mail list. On July 1, 2010 Gavin and I had lunch with Marvin Parnes, U-M's Associate Vice President for Research (the Computing Center reported to the VP for Research until the U-M created the Information technology Division in the 1980s). Gavin and I have known Marvin for a long time and had worked with him to make network connected personal computers available in U-M's student housing (they don't like to call them dorms) in the days before Marvin moved to the VP for Research's Office. At our first meeting, Marvin was very supportive of helping to make MTS, including a runnable version, more widely available. He asked me to write down what we wanted to do.
It took me longer to get that done than it should have, but I got something written and over to Marvin in early 2011. Marvin got Jack Bernard, U-M's Associate General Counsel involved. Jack had a history with the Information Technology Division from the time before he went to law school. He, like pretty much everyone else we've approached, was very supportive. It was Jack who suggested using the Creative Commons Attribution License (CC-BY) and referred me to an expert on the CC licenses at the U-M Library who encouraged us to avoid the NonCommercial (NC) and ShareAlike (SA) provisions of the license, which we did and Jack approved. Marvin also checked with the U-M's CIO, Laura Patterson, and with the U-M's Associate Vice President for Research CyberInfrastructure, Dan Atkins, and they were both supportive. It took until July 2011 for Marvin and Jack to write a joint letter making this an official project of the Office of the Vice President for Research in association with the Office of the General Counsel and giving permission to make MTS available. There was never any problem along the way, but Marvin and Jack are busy people and it was hard to argue that resurrecting a time-sharing operating system that the University hadn't been using for 15 years should be a high priority.
Once we had official permission, it took us until November 2011 to send several .tar.gz archives to Al at Bitsavers. Al made the MTS distribution materials available on December 22, 2011. The MTS distribution materials were added to U-M's Deep Blue digital archive on January 8, 2012. And the rest, as they say, is history.
While it took a long time to make the MTS materials available, there was never any opposition to doing so. In fact there was often enthusiastic support. I'm not sure why this was so. Perhaps because the University of Michigan and the other sites that developed and used MTS are all academic rather than for-profit commercial organizations. Perhaps because these sites stopped using MTS many years ago. Perhaps because U-M used MTS for 29 years and people were proud of what had been accomplished and were happy to see that history preserved. Perhaps because many of the people involved in making the decisions knew one another and were friends. Or perhaps some combination of all of this.
I would encourage others who were involved to add their views and to make corrections to my account. As Tom Jacobsen suggested, I will eventually make this or an edited version of this available on the MTS Archive site.
On Jan 25, 2012, at 6:26 PM, Dave wrote:
On Jan 25, 2012, at 7:05 PM, Jeff Ogden wrote:
Way back when I was a young pup, either in college or after that but before I started my career, I got to use an operating system called MTS. That stands for Michigan Terminal System. It was created to run on IBM (and later Amdahl) mainframes, when U of M got tired of waiting for IBM to deliver a multi-user operating system. Like most code that old, it was an interesting combination of ideas that have since been abandoned because they were stupid, ideas that were ahead of their time, and ideas that were somewhere in between. Here are some of the more interesting ideas.
While I was still using MTS, they added a macro system - what we would now think of as a shell scripting language. One of the very first uses of this macro system was to sythesize a hierarchical directory structure on top of the flat one native to MTS. I really wish I could remember the name of the author, to give credit. He was a Computing Center consultant, and this would have been in 1985 or so, if anybody wants to help me out. It was a pretty slick combination of naming conventions and macros, and I think it made many users' lives easier.
The reason I started thinking about MTS is that I see people doing the exact same things now - nearly thirty years later - to simulate a hierarchical namespace on top of the flat one provided by most object stores. Let me repeat something I've said many times before, in many ways: flat namespaces weren't just crap in DOS, they were crap in MTS even before that and they're still crap today. Crap, I say. Anybody who implements a supposedly modern file/object store with a flat namespace is simply screwing their users to suit their own convenience. The scalability arguments don't hold water, because the scalability issues mostly have to do with the operations that you have to support (e.g. atomic rename) than with whether or not you have nested directories. This is something that has to be built into the data store, with the necessary recursive name resolution done one place one time by people who understand that data store, instead of being done ten incompatible ways by ten different outsiders. Even quite smart people can trip when they try to bolt on a hierarchical structure after the fact.
Users have shown over and over again that they want flexibility to organize and reorganize their data, in ways richer than a flat or even single-level hierarchy will allow. Maybe there's an even better way, but so far none of the attempts to replace nested directories with tags or links or database-like queries seem to have gained much traction. Until someone comes up with something better, the nested-directory structure should be considered a minimum standard for anything that's supposed to replace the traditional filesystem.
A comment posted by dlambrig on 1 January 2014:
My school used MTS. The mainframes hosting MTS were housed under a church. The school had refurbished the church into a computer lab. Those mainframes generated enough heat to keep the entire building warm in the winter. MTS lasted roughly from 1976-1995. In the beginning it was hailed as a timesharing system superior to rivals (TSO etc.). Apparently IBM was very upset MTS was chosen and warned administrators that graduates would “not have the right skills”. By the late 80s the computer science department was in open rebellion with IT to replace it with UNIX.
https://news.ycombinator.com/item?id=9401124 on 19 April 2015