Title page for ETD etd-02022010-020103


Type of Document Master's Thesis
Author Haugh, J. Steven
URN etd-02022010-020103
Title The design of a virtual fact base for Prolog
Degree Master of Science
Department Computer Science and Applications
Advisory Committee
Advisor Name Title
Fox, Edward Alan Committee Member
Roach, John W. Committee Member
Shaffer, Clifford A. Committee Member
Keywords
  • Prolog (Computer program language)
Date of Defense 1991-04-08
Availability restricted
Abstract
The fact and rule list internal to Prolog is capable of handling as many facts as available memory resources permit. A solution to this limitation is to store facts on disk, retrieving them into a main memory database buffer only as needed. Allocating a fixed portion of main memory to buffer database facts frees up scarce main memory for more frequently accessed rules and data structures internal to Prolog. The Prolog Database System built in connection with this project transparently stores and retrieves facts on disk and evaluates them in the order they were asserted allowing for the transfer of existing small scale prototypes into large scale production systems.

Since existing relational database techniques were not designed to function in a Prolog environment where facts are evaluated in database facilities were designed, developed, and integrated into Prolog. These database facilities include a unique page replacement policy designed to minimize expensive page faults during the execution of a Prolog program. The look ahead page replacement policy looks ahead on database pages while they are in main memory in order to determine whether they are likely to be accessed again in the future. In this way, a near optimal working set of database pages is maintained in the database buffer, assisting with minimizing expensive page faults.

Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
[VT] LD5655.V851_1991.H294.pdf 3.36 Mb 00:15:32 00:07:59 00:06:59 00:03:29 00:00:17
[BTD] next to an author's name indicates that all files or directories associated with their ETD are accessible from the Virginia Tech campus network only.

Browse All Available ETDs by ( Author | Department )

dla home
etds imagebase journals news ereserve special collections
virgnia tech home contact dla university libraries

If you have questions or technical problems, please Contact DLA.