Browse Prior Art Database

IPLable S/370 I/O CONFIGURATOR

IP.com Disclosure Number: IPCOM000036471D
Original Publication Date: 1989-Oct-01
Included in the Prior Art Database: 2005-Jan-29
Document File: 2 page(s) / 13K

Publishing Venue

IBM

Related People

Bauman, ML: AUTHOR

Abstract

Disclosed is a software algorithm that commences an optimally effective and timely S/370 I/O device configuration process.

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IPLable S/370 I/O CONFIGURATOR

Disclosed is a software algorithm that commences an optimally effective and timely S/370 I/O device configuration process.

The term, 'I/O configuration', is used here to mean the process of deriving a map of occupied device addresses and attached device types in an automatic fashion.

The S/370 architecture provides for matching I/O device rates (comparatively slow) with CPU rates (comparatively fast) via I/O channels. I/O channels operate independently of the CPU and independently of one another, thus allowing parallel (simultaneous) activities to go on in the CPU and I/O subsystem. Additionally, I/O channels may attach one or more control units to a system where the control units have independent processing capabilities, thus allowing parallel (simultaneous) activities to go on outboard of the channel.

To optimize the effectiveness and timeliness of the I/O configuration process, the algorithm commencing the process takes advantage of the parallelism implemented within the S/370 architecture. The algorithm is structured in the following manner:
1. Start 1st device on 1st control unit on 1st channel
2. Start 1st device on 1st control unit on 2nd channel
3. ...and so on for rest of channels on system
4. Start 1st device on 2nd control unit on 1st channel
5. Start 1st device on 2nd control unit on 2nd channel
6. ...and so on for rest of channels, and rest of control

units on channel
7. Start 2nd device on 1st control unit on 1st chann...