Browse Prior Art Database

Simulation Time Management

IP.com Disclosure Number: IPCOM000080240D
Original Publication Date: 1973-Nov-01
Included in the Prior Art Database: 2005-Feb-27
Document File: 2 page(s) / 50K

Publishing Venue

IBM

Related People

Schor, MI: AUTHOR

Abstract

A system for the simulation of a discreetly configurable computer subsystem is shown in Fig. 1. The object of the simulation is to test the interactions of the models, each of which has one or more interfaces, enabling the interconnection of the models in diverse configurations.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 80% of the total text.

Page 1 of 2

Simulation Time Management

A system for the simulation of a discreetly configurable computer subsystem is shown in Fig. 1. The object of the simulation is to test the interactions of the models, each of which has one or more interfaces, enabling the interconnection of the models in diverse configurations.

A necessary ground rule for designing independent models to operate in this configurable environment, is that they only interact with each other through their interconnected interfaces. Previously, this interaction involved the establishing of various monitoring loops in each model, to periodically check various simulated input lines to detect a change in condition. This continual scanning of the interfaces has been shown to require considerable CPU time when simulating.

The solution of Fig. 2 comprises Asynchronous Wait Queue Control Blocks (AWQCB's), a "Wait for" command, and a "Schedule" command. An AWQCB is associated, by convention, with one or more signals in the connecting interface. A discipline is imposed on each user of the interface as follows:
(1) Any user wishing to be notified when a signal associated

with a particular AWQCB changes, issues a "Wait for" command

specifying that AWQCB.
(2) Any user changing a signal having an AWQCB associated with

it must issue a "Schedule" command to that AWQCB, in order

to notify all models that were waiting for that signal to

change.

The "Schedule" command has the efiect of indirectly initiating routines in all ot...