Houston Automatic Spooling Priority

See also: Spooling

The Houston Automatic Spooling Priority Program, commonly known as HASP, is an extension of the IBM OS/360 operating system and its successors providing extended support for "job management, data management, task management, and remote job entry."[1]:p.1–3

History

OS/360 included spooling routines, called reader/interpreters and output writers.[2] Each reader/interpreter was "responsible for reading one input job stream" – that is one input device. Likewise each output writer was responsible for controlling one printer or punch. Spooled data were stored in OS temporary datasets controlled by standard OS services. Each reader/interpreter or output writer was a separate operating system task in its own partition or region.[3] A system with a large number of readers, printers, and punches might have a large number of spooling tasks.

HASP was developed by IBM Federal Systems Division contractors at the Lyndon B. Johnson Space Center in Houston. The developers were Tom Simpson and Bob Crabtree. HASP was a program that ran on a mainframe, and performed functions such as: scheduling, control of job flow, spooling and printing/punching. HASP had no support for IBM System/360 Operating System Remote Job Entry, 360S-RC-536, but provided roughly equivalent facilities of its own.

In HASP II V3, NIH created the shared spool capability for HASP that was used by many mainframe sites. It allowed each HASP system to share a common spool and checkpoint. This enabled workload balancing in a multi-mainframe environment. In HASP II V4, Mellon Bank - Don Greb & Dave Miko moved shared spool to this version and carried it forward into JES2 multi-access spool (IBM's formal support of HASP in MVS). Over 350 copies of the HASP II V4 shared spool mods were distributed around the world. The shared spool Mellon Mods were added to the SHARE distribution process so they could be more widely accessed.

The program was sometimes referred to under various other names, but there is no indication of IBM ever using them in official documents.

The program became classified as part of the IBM Type-III Library. It had a competitor, ASP which ran on one mainframe and controlled scheduling of other attached mainframes. ASP later became JES3.

In MVS, HASP became JES2, one of two Job Entry Subsystems. It was many years before the HASP labels were removed from the JES2 source, and the messages issued by JES2 are still prefixed with "$HASP".

A modified version of HASP was used to provide batch spooling and remote job entry services for the Michigan Terminal System during the late 1960s, 1970s, and 1980s.[4][5]

Program organization

HASP bypassed most operating system services with code specially tailored for efficiency. HASP operated as a single operating system task[1] and used cooperative multitasking internally to run processors to perform tasks such as running card readers, printers, and punches, managing the spool files, communicating with the system operator, and driving multiple communication lines for remote job entry.

Hasp was written entirely in System/360 assembler and a typical HASP system might require 86KB of memory, which could be virtual memory on OS/VS systems.[6]

Remote job entry

HASP supported IBM terminals such as 2770, 2780, and 3780, but additionally provided support for multi-leaving communication with intelligent workstations such as the IBM 1130 and the System/360 Model 20. Multi-leaving is "fully synchronous, pseudo-simultaneous, bi-directional transmission of a variable number of data streams between two or more computers utilizing binary-synchronous communications facilities."[1]:p.1–8

Third party vendors developed a variety of 2770/2780/3780 simulators and Multi-leaving implementations for use with HASP and ASP. Some of these vendors incorrectly referred to their products as HASP emulators, but the products were actually terminals that talked to HASP; they did not perform any of the functions of HASP.

Job log

HASP job log output provided a summary of the resources used for the job (output appeared in all caps):

See also

Notes

  1. 1 2 3 IBM (March 1973). OS/VS2 HASP II Version 4 Logic, Program Number 370H-TX -001 (PDF). First Edition, Revised September 15, 1976, by TNLs SN25-0122 and SN27-1555. GY27-7255-0.
  2. ↑ IBM (1965). IBM Operating System/360 Concepts and Facilities (PDF). pp. 59–62. C28-6535-0.
  3. ↑ However, RJE and the later CRJE called the Reader/Interpreter as a subroutine and performed the functions of an output writer within its own partition/region.
  4. ↑ HASP II (MTS Version) Operator's Guide, J.H. Hansen and S.M. Donnelly, Computing Center, University of Michigan, 20 April 1988, 122 pages
  5. ↑ "Resource Manager Printing Comes to U-M (replacing HASP)", U-M Computing News, Vol. 5 No. 1 (8 January 1990), University of Michigan (Ann Arbor), page 19
  6. ↑ IBM (March 1973). OS/VS2 HASP II Version 4 System Programmer's Guide, Program Number 370H-TX-001 (PDF). First Edition revised September 15, 1976, by TNLs GN25-0121 and GN27-1553. GC27-6992-0.

References

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