Browse Prior Art Database

High-Performance Multiple-Priority Event Queue in Object Oriented Analysis Implementation

IP.com Disclosure Number: IPCOM000116317D
Original Publication Date: 1995-Aug-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 2 page(s) / 59K

Publishing Venue

IBM

Related People

Chen, C: AUTHOR [+2]

Abstract

A system with hard real-time constraints must respond to external stimulus within a fixed period of time. Different external stimuli force the system to successfully respond to each one of them under variant real-time constraints. A discriminating scheduling scheme is required for a high performance real-time system to operate in this environment. For a real-time system developed using a hybrid Object Oriented Analysis (OOA) methodology, two key factors in object communication have direct impact on the system's overall response time to external stimulus: 1. The time required by a system event dispatcher to validate a specific object instance's state transition caused by an event 2. The time required by an event waiting in an event queue for its turn to be dispatched

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 54% of the total text.

High-Performance Multiple-Priority Event Queue in Object Oriented
Analysis Implementation

      A system with hard real-time constraints must respond to
external stimulus within a fixed period of time.  Different external
stimuli force the system to successfully respond to each one of them
under variant real-time constraints.  A discriminating scheduling
scheme is required for a high performance real-time system to operate
in this environment.  For a real-time system developed using a hybrid
Object Oriented Analysis (OOA) methodology, two key factors in object
communication have direct impact on the system's overall response
time to external stimulus:
  1.  The time required by a system event dispatcher to validate a
       specific object instance's state transition caused by an event
  2.  The time required by an event waiting in an event queue for its
       turn to be dispatched

      An external stimulus corresponds to a specific thread of
control within the system.  A thread of control consists of a
sequence of events and object state executions.  For the system to
promptly operate on critical threads of control, the events
associated with critical threads must be given higher priority than
those not with critical threads.  Otherwise, the event dispatcher
simply processes each event on a first-come-first-served basis, which
causes unacceptable delays and subsequent system failure.

      Disclosed is an event dispatch mechanism that supports
prioritized threads of control in an object oriented sy...