Synchronous parallel emulation and discrete event simulation system with self-contained simulation objects and active event objects

• US 5,794,005 A
• Filed: 12/12/1994
• Issued: 08/11/1998
• Est. Priority Date: 01/21/1992
• Status: Expired due to Fees

• Current Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Original Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Inventors: Steinman, Jeffrey S.
• Primary Examiner(s): Kim, Kenneth S.
• Application Number:
  US08/363,546
• Time in Patent Office: 1,338 Days
• Field of Search: 395/500, 395/683, 395/557, 364/140, 364/578
• US Class Current: 703/17
• CPC Class Codes: G06F 30/20 Design optimisation, verification or simulation optimisation, verification or simulation of circuit designs G06F30/30

Abstract

The present invention is embodied in a method of performing object-oriented simulation and a system having interconnected processor nodes operating in parallel to simulate mutual interactions of a set of discrete simulation objects distributed among the nodes as a sequence of discrete events changing state variables of respective simulation objects so as to generate new event-defining messages addressed to respective ones of the nodes. The object-oriented simulation is performed at each one of the nodes by assigning passive self-contained simulation objects to each one of the nodes, responding to messages received at one node by generating corresponding active event objects having user-defined inherent capabilities and individual time stamps and corresponding to respective events affecting one of the passive self-contained simulation objects of the one node, restricting the respective passive self-contained simulation objects to only providing and receiving information from the respective active event objects, requesting information and changing variables within a passive self-contained simulation object by the active event object, and producing corresponding messages specifying events resulting therefrom by the active event objects.

Claims

1. In a system of interconnected processor nodes operating in parallel to simulate mutual interactions of a set of discrete simulation objects distributed among said nodes as a sequence of discrete events changing state variables of respective simulation objects so as to generate new event-defining messages addressed to respective ones of said nodes, a method of performing object-oriented simulation at each one of said nodes comprising:

assigning passive self-contained simulation objects to each one of said nodes;

responding to messages received at one node by generating corresponding active event objects having user-defined inherent capabilities and individual time stamps and corresponding to respective events affecting one of said passive self-contained simulation objects of said one node;

restricting said respective passive self-contained simulation objects to only providing and receiving information from said respective active event objects;

requesting information and changing variables within a passive self-contained simulation object by said active event object; and

producing corresponding messages specifying events resulting therefrom by said active event objects.

2. A system of interconnected processor nodes operating in parallel to simulate mutual interactions of a set of discrete simulation objects distributed among said nodes as a sequence of discrete events changing state variables of respective simulation objects so as to generate new event-defining messages addressed to respective ones of said nodes, said system performing object-oriented simulation at each one of said nodes and comprising:

means for assigning passive self-contained simulation objects to each one of said nodes;

means for responding to messages received at one node by generating corresponding active event objects having user-defined inherent capabilities and individual time stamps and corresponding to respective events affecting one of said passive self-contained simulation objects of said one node;

means for restricting said respective passive self-contained simulation objects to only providing and receiving information from said respective active event objects;

means for requesting information and changing variables within a passive self-contained simulation object by said active event object; and

means for producing corresponding messages specifying events resulting therefrom by said active event objects.

3. A system of interconnected processor nodes operating in parallel for simulating mutual interactions of a set of discrete simulation objects distributed among said nodes as a sequence of discrete events changing state variables of respective simulation objects so as to generate new event-defining messages addressed to respective ones of said nodes, said system performing object-oriented simulation at each one of said nodes and comprising:

passive self-contained simulation objects assigned to each one of said nodes; and

corresponding active event objects generated in response to messages received at one node, said active event objects user-defined inherent capabilities and having individual time stamps and corresponding to respective events affecting one of said passive self-contained simulation objects of said one node, wherein said active event objects request information and change variables within a passive self-contained simulation object and produce corresponding messages specifying events resulting therefrom;

wherein said respective passive self-contained simulation objects are restricted to only providing and receiving information from said respective active event objects.

4. A system of interconnected processor nodes operating in parallel comprising:

a set of discrete simulation objects distributed among said nodes;

a computer program operating on said system for simulating mutual interactions of said set of discrete simulation objects as a sequence of discrete events changing state variables of respective simulation objects so as to generate new event-defining messages addressed to respective ones of said nodes;

wherein said computer program performs object-oriented simulation at each one of said nodes and comprises,

passive self-contained simulation objects assigned to each one of said nodes, and

corresponding active event objects generated in response to messages received at one node, said active event objects having user-defined inherent capabilities and individual time stamps and corresponding to respective events affecting one of said passive self-contained simulation objects of said one node, wherein said active event objects request information and change variables within a passive self-contained simulation object and produce corresponding messages specifying events resulting therefrom;

wherein said respective passive self-contained simulation objects are restricted to only providing and receiving information from said respective active event objects.

5. A computer-readable medium for causing a computer system of interconnected processor nodes operating in parallel to function as a parallel processing system, comprising:

a computer-readable storage medium;

a computer program stored on said medium;

a set of discrete simulation objects distributed among said nodes;

wherein said computer program operates on said system for simulating mutual interactions of said set of discrete simulation objects as a sequence of discrete events changing state variables of respective simulation objects so as to generate new event-defining messages addressed to respective ones of said nodes and wherein said computer program performs object-oriented simulation at each one of said nodes and comprises,

passive self-contained simulation objects assigned to each one of said nodes, and

corresponding active event objects generated in response to messages received at one node, said active event objects having user-defined inherent capabilities and individual time stamps and corresponding to respective events affecting one of said passive self-contained simulation objects of said one node, wherein said active event objects request information and change variables within a passive self-contained simulation object and produce corresponding messages specifying events resulting therefrom;

wherein said respective passive self-contained simulation objects are restricted to only providing and receiving information from said respective active event objects.