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                   MTS:    The Michigan Terminal System
0                               April 1987
0         The University of Michigan, acting as agent for  the  group
     of  universities  which  have  jointly  developed  the  Michigan
     Terminal System (MTS), has established a  policy  governing  the
     licensed  use  of  MTS by other organizations.  The policy is to
     make MTS  available  to  academic  institutions  as  a  licensed
     program  for  an  annual  fee  of  $5,000.  For other non-profit
     organizations,  the  annual  fee  is  $10,000;  for   commercial
     organizations,  the  annual fee is $25,000.  In all cases, there
     are restrictions imposed by the license agreement including  the
     stipulation  that  the  licensee shall not provide access to MTS
     under  circumstances  that  could  be  construed  as   providing
     commercial   computing  services.   During  the  annual  license
     period, the licensee will receive one copy of the  full  set  of
     MTS  distribution  tapes, any incremental distributions prepared
     during the year (generally one  or  two),  written  installation
     instructions, and two copies of the current user documentation.
0         Since we do not have a large system support staff available
     to  help organizations desiring to run MTS, we suggest that such
     organizations have system programmers who are able to do routine
     maintenance and diagnose  simple  problems.   The  existing  MTS
     installations  are each quite self sufficient, some of them with
     as few as two or three system programmers responsible for MTS.
-    Background of MTS
+    __________ __ ___
-         Development of MTS was begun at the University of  Michigan
     in  the  mid-1960s  specifically to provide general, interactive
     computing services on the IBM 360/67 computer; MTS has  been  in
     production  use  in  Ann  Arbor since 1967.  The Universities of
     British Columbia, Alberta, and Newcastle  upon  Tyne  (England),
     and  Wayne  State University have all been using MTS for over 10
     years.  In addition,  Rensselaer  Polytechnic  Institute,  Simon
     Fraser  University,  a  research institute in Brazil, and Durham
     University (England) all use MTS as  their  primary  system  for
     research  and  instruction.   MTS  is currently being run on the
     following computing systems:  Amdahl  5860,  5870,  470V/8,  IBM
     3090-400  (with vector facility), 3081G, 3081D, 3033N, and 4361.
     In addition MTS has been tested on or was used for production on
     the following machines: Amdahl 470V/6, 470V/7, 5890, IBM  3033U,
     370/148, 370/168, 370/158, 4341, and NAS 9060, and XL.
0         MTS  originally was designed for virtual memory interactive
     service only.  The batch capability was added after a few  years
     when  it  became  clear  that  MTS  would  be used in production
     environments where it was necessary to  be  able  to  run  large
     numbers of low-overhead batch jobs.  Fortunately, this has meant
     that  interactive  support and virtual memory have not had to be
     retrofitted into  the  system  (as  in  the  case  of  some  IBM
     systems).   At the University of Michigan, interactive access is
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     used for over 85 percent of all jobs; batch being primarily used
     for those jobs which users are willing  to  defer  to  off-hours
     when lower charge rates are in effect.
0         Large  private  paged  virtual  memories (currently up to 9
     megabytes for each user) have been a "way of life" in MTS  since
     the  beginning.   MTS  users  have always been able to run large
     programs and programs with large arrays without being  concerned
     with  overlays,  a  concept  which has never existed in MTS.  In
     addition, MTS itself and many  system  utilities  and  compilers
     (those  which are re-entrant) reside in shared, paged, read-only
     virtual memory (VM).  Because of this, most MTS commands require
     less than a few dozen pages of private VM to execute, whereas  a
     FORTRAN-G  compilation  may take 60 to 70 pages of VM since that
     compiler is not re-entrant and thus must be loaded into  private
     VM for each user.
0         MTS  provides  a  comprehensive  shared-access  file system
     which is not compatible with IBM software  systems.   The  user-
     level  program environment is also different from IBM systems in
     several respects, although many programs written to run  in  IBM
     systems will work with little or no modification.  The format of
     object  decks in MTS is essentially compatible with IBM, but the
     SVC instructions are completely different (and not normally used
     by MTS user-level programs).   In  addition,  MTS  provides  two
     programs  to  emulate the OS/VS application program environment;
     they allow  many  OS/VS  application  programs  to  run  without
     modification.
0         MTS  supports  a  comprehensive  set of language processors
     including  FORTRAN  (G,  H,  VS,  WATFIV,  and  IF),  PL/I   (F,
     Optimizing, and PL/C), COBOL (U, VS, and WATBOL), Basic (MTS and
     Waterloo),    Pascal    (VS   and   several   others),   APL/VS,
     Snobol/Spitbol,  Algol  W,  CSMP,  GPSS,  LISP,   SIMSCRIPT   2,
     Reduce/3,  SLIP,  and  assemblers  for the IBM 370 (G and H) and
     various  other  computers  including  PDP-8,  PDP-11,  and  many
     microprocessors.
0         MTS  also  provides a state-of-the-art context editor which
     includes full-screen editing through an  interface  to  the  MTS
     device-independent screen support routines which can function on
     several  different  terminal  types.   This screen management is
     also used by several other MTS components, including  an  online
     HELP facility, and is available to user-level programs.
0         A  comprehensive  message  system  is provided by MTS.  The
     message system has a network interface allowing messages  to  be
     sent   to  and  received  from  other  host  systems.   Two  MTS
     conferencing programs are available to licensees;  one,  *FORUM,
     is  included  as  a  part of the distributed system.  A powerful
     conditional command and macro processor package was added to the
     system in 1983.
0         Much of the development of MTS is done jointly  with  other
     MTS  installations.  Representatives of these installations meet
     once each year for a workshop at which most  of  the  discussion
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     relates  to  what  new  features and changes are desired and who
     will do the design and implementation.
-    Machine Requirements
+    _______ ____________
0         MTS requires an IBM 370 compatible machine  (including  the
     30xx  machines)  with  at  least two megabytes of memory and the
     following features:
0        Floating Point
         Universal Instruction Set
         CPU-timer and Clock-Comparator
         Translation with 1M segments and 4K pages
         Conditional-Swapping
         PSW-Key-Handling
         Channel Indirect Addressing on all channels
         Clear I/O on all channels
0    It  will  make  use  of  the  following  features  if  they  are
     available:
0        Extended precision floating point
         Vector facility
         Direct control (limited use)
         Branch and Save
         Fast release on channels
         Invalidate Page Table Entry
         Common Segment Facility
0    Other  features  are  not used, unless user programs make use of
     them.  MTS will likely be extended in the future to make use  of
     the Dual Address Space feature.  It has been changed to run with
     either  1M  or 64K segments for the IBM 30xx and will operate in
     either  370  or  XA  (Extended  Architecture)  modes,  including
     multiple  processor  support,  but  these  changes  are  not yet
     available in the standard distribution system.
0         MTS can run under VM/370, but  performance  is  poor  under
     heavy load.  As distributed, MTS will not make use of any of the
     features  of  VM  to  enhance  performance  of  guest  operating
     systems, although versions of MTS have been prepared in the past
     that do so.
0         The MTS file system normally  uses  IBM  3330  and/or  3350
     compatible  disks  in  any combination although it also supports
     older types of disks.  Support has recently been added  for  IBM
     3370,  3340,  3344,  3375, 3380 and Amdahl 6280 disks, but these
     are not yet available in the standard distributed system.
0         MTS also provides support for the Xerox 9700 page  printer,
     the  Autologic  APS-5 phototypesetter, and for both IBM and ANSI
     standard magnetic tape labeling/blocking and the normal IBM unit
     record equipment.
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     MTS Performance at the University of Michigan
+    ___ ___________ __ ___ __________ __ ________
0         On  a  typical  weekday  afternoon  at  the  University  of
     Michigan with 400+ concurrent interactive terminal users and 125
     batch  jobs  per hour, there are usually about 35,000 pages (123
     megabytes) of total VM in use, of which about 31,000  pages  are
     private  and the remainder shared.  An average user has about 90
     pages of private VM.   There  are  usually  at  least  60  users
     running  large  programs  (150  to  500  pages  of VM) and a few
     running even larger programs (500  to  1,000  pages).   Our  64-
     megabyte  IBM  3090-200  is  about  50 percent saturated at this
     load.
0         For primary paging devices, we currently use one Intel 3825
     and two Intel 3805s each with about 11,000 4k pages and each  on
     a  separate  block  multiplexor  channel.   These devices run in
     native mode, not compatible with an  IBM  2305.   This  hardware
     provides  about  90  megabytes  of  high-speed backing store and
     permits paging rates of approximately 450 page reads per  second
     to   be  achieved  easily  although  typical  levels  in  actual
     operation are much lower.  The associated page writes amount  to
     approximately  300  additional  pages per second at peak levels.
     In addition, MTS can also use IBM 2305s for primary  paging  and
     support   for  expanded  storage  on  a  3090  is  being  added.
     Generally, a disk is also used as a secondary paging device  and
     MTS can be run using only disks for paging if necessary.
0         We  have  a  mixture  of  6280s and 3380s with a total file
     system capacity of about 18,100 megabytes currently.
0         Performance  data  is  also  available  for  other   system
     configurations.  At Michigan, MTS also runs on a second 3090-200
     and on an IBM 4361.
-    Terminal Access and Networking
+    ________ ______ ___ __________
0         Terminal  support  is  provided  using  IBM  3270s, Memorex
     1270s, and, at most MTS installations, locally developed network
     processors (generally PDP-11 based).  At Michigan, we have  five
     PDP-11  network  nodes  which  are  used to interface MTS to the
     UMnet/Merit computer network  and  to  Telenet.   These  network
     processors  allow  approximately  600  concurrent  terminals  to
     access MTS.  The network provides access from a diverse  set  of
     ASCII   terminals   (including   micros  and  other  intelligent
     terminals) to several computers  on  our  campus  including  the
     central  MTS  systems.   It  is  composed  of  PDP-11 and LSI-11
     switching and terminal access nodes linked together  by  twisted
     pair  and  Ethernets  operating at speeds up to 1.5 Mbps.  It is
     interconnected with  the  regional  Merit  network  and  Telenet
     allowing  terminals  on the network to access other computers in
     the state and beyond.
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          The UMnet software  can  be  separately  licensed  and  the
     hardware  purchased  as  can  the MTS network software from some
     other MTS installations.
0         In addition, we have several dozen local  3278s  (MTS  does
+                                            _____
     not support remote 3270 terminals).
-    Obtaining Additional Information
+    _________ __________ ___________
0         Further  details  on MTS, including information about user-
     level  documentation  and  the  MTS  License  Agreement  can  be
     obtained by contacting the following:
-      MTS               Michael T. Alexander,    (313) 763-4890
                         James M. Bodwin,         (313) 763-3733
                         Jon C. Sell,             (313) 764-5324
0      License policy    Leonard J. Harding,      (313) 763-6054
0      Distribution      Suzan W. J. Alexander,   (313) 763-4906
0      Address           University of Michigan
                         Computing Center
                         535 W.  William St.
                         Ann Arbor, MI 48103-4943
