MUSIC/SP
This article includes a list of general references, but it lacks sufficient corresponding inline citations. (July 2021) |
S/370, and 4300-series mainframes | |
Preceded by | RAX |
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History of IBM mainframe operating systems |
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MUSIC/SP (Multi-User System for Interactive Computing/System Product; originally McGill University System for Interactive Computing) was developed at McGill University in the 1970s from an early IBM time-sharing system called RAX (Remote Access Computing System).[1][2]
The system ran on IBM
.MUSIC was originally designed as a stand-alone operating system but with the advent of IBM's virtual machine facility,
History
- 1966 – IBM Remote Access Computing System (RAX) released.
- 1972 – McGill's RAX modifications accepted by IBM for distribution as "Installed User Program" under the name of "McGill University System for Interactive Computing" (MUSIC).[4]
- 1978 – MUSIC 4.0 Major change to file system providing longer file names and advanced access control.
- 1981 – MUSIC 5.0 Support for IBM 4300 series CPUs and FBA disks.
- 1985 – MUSIC/SP 1.0 Adopted by IBM as "System Product". Support for virtual memory.
- 1990 – MUSIC/SP 2.2, described by IBM as having "significant enhancements."[5]
- 1991 – MUSIC/SP 2.3 Internet support and tree-structured file system.
Over the years the following people contributed to the MUSIC and MUSIC/SP systems. Roy Miller, Alan Greenberg, Wilf Mandel, Dave Edwards, Nelson Nguyen, Kevin McNamee, Don Farnsworth (IBM), Dean Daniele (IBM), Glen Matthews, Linda Chernabrow, Frank Pettinicchio, Earl Lindberg, Pierre Goyette, Kathy Wilmot, Simon Fulleringer, David Thorpe, Gerald Ratzer, Harry Williams (Marist College), Dave Juraschek (Northern Virginia Community Colleges), Christian Robert (Ecole Polytechnique), Simone Spiller, Silvino Mezzari, and Mike Short.
Features
File system
The MUSIC/SP file system was unique in a number of respects. There was a single system-wide file index. The owner's
Virtual memory
The initial versions of the system provided no support for virtual memory and address translation. Only one active user could reside in core memory at any time. Swapping (to disk) was used to time-share between different users, and a variable-length timeslice was used. Virtual memory support was introduced in 1985. This allowed multiple users to be in core memory at the same time, removed many of the restrictions in the size of the programs that could be run and provided a significant performance improvement. System performance was also improved by pre-loading commonly used modules into virtual memory at startup time where they could be available to all users simultaneously.
Programming languages
The system was designed to support academic computing and the teaching of computer science, so a rich suite of programming languages was available. The system
E-mail and the Internet
E-mail was one of the major applications on MUSIC/SP. The e-mail interface initially provided access to local e-mail. As the networks developed, this was expanded to provide access to BITNET and Internet based e-mail. MUSIC/SP did not have direct access to the Internet until 1990, when the University of Wisconsin WiscNet TCP/IP code was ported to the system, allowing the system to provide access to all Internet services.
Compatibility with other IBM systems
A major feature of the system was its ability to run programs that were designed to run on IBM's mainstream operating system (MVS). This was accomplished using an MVS emulator that intercepted system calls at the Supervisor Call instruction (SVC) level. Most third-party applications ran in this mode. Rather than write their own version of an application, the MUSIC/SP developers would usually start from the MVS version and rebuild it to run in MVS emulation mode. Since the MVS emulation was a small subset of the real thing, the applications generally ran more efficiently on MUSIC/SP.
Other features
One major advantage the system had in educational environments was that through the use of special lines called "control cards" at the top of a file, source files for any supported language could be automatically directed to the appropriate compiler (Fortran being the default), compiled, linked, and executed, (with compilation, linkage, and execution options also specified in control cards) simply by entering the filename on a command line.
A wide variety of
Emulation
The Sim390 emulator contains a demonstration system of MUSIC/SP. It is freely available and runs on Microsoft Windows.[6] The demonstration system will also run under Hercules.
See also
- Michigan Terminal System
- Multics
- time-sharing
- Time Sharing Option (TSO)
- VPS/VM an offshoot of Music
- Time-sharing system evolution
References
- ^ Miller, Roy Watt. "MULTIPLE REGIONS FOR THE MCGILL-RAX TlME-SHARING SYSTEM". Library and Archives Canada. Retrieved April 29, 2021.
- ^ "Boston University's RAX Library". Cryptosmith.com. January 12, 2012. Retrieved April 29, 2021.
- ^ "5749-010 - VIRTUAL MACHINE FACILITY/370 (VM/370)". January 12, 1989. Retrieved July 19, 2021.
- OCLC 937543344.
- ^ "Announcement Summary". February 20, 1990.
significant enhancements ,, from 2.1, announced May 2, 1989.
- ^ Sim390 Mainframe Emulator - Home