The New Jersey Institute of Technology's
Electronic Theses & Dissertations Project

Title:	Identifying and exploiting concurrency in object-based real-time systems
Author:	Yu, Guohui
View Online:	njit-etd1996-045 (xvii, 148 pages ~ 5.9 MB pdf)
Department:	Department of Computer and Information Science
Degree:	Doctor of Philosophy
Program:	Computer and Information Science
Document Type:	Dissertation
Advisory Committee:	Welch, Lonnie R. (Committee chair) Hammer, Dieter K. (Committee member) Kurfess, Franz J. (Committee member) McHugh, James A. (Committee member) Ng, Peter A. (Committee member) Rossak, Wilhelm (Committee member) Zhao, Wei (Committee member)
Date:	1996-01
Keywords:	Parallel processing (Electronic computers) Object-oriented methods (Computer science) Real-time data processing.
Availability:	Unrestricted
Abstract:	The use of object-based mechanisms, i.e., abstract data types (ADTs), for constructing software systems can help to decrease development costs, increase understandability and increase maintainability. However, execution efficiency may be sacrificed due to the large number of procedure calls, and due to contention for shared ADTs in concurrent systems. Such inefficiencies are a concern in real-time applications that have stringent timing requirements. To address these issues, the potentially inefficient procedure calls are turned into a source of concurrency via asynchronous procedure calls (ARPCs), and contention for shared ADTS is reduced via ADT cloning. A framework for concurrency analysis in object-based systems is developed, and compiler techniques for identifying potential concurrency via ARPCs and cloning are introduced. Exploitation of the parallelizing compiler techniques is illustrated in the context of an incremental schedule construction algorithm that enhances concurrency incrementally so that feasible real-time schedules can be constructed. Experimental results show large speedup gains with these techniques. Additionally, experiments show that the concurrency enhancement techniques are often useful in constructing feasible schedules for hard real-time systems.