29185449
Performance Analysis and Scalability of the ThreadmanTM Thread Manager
697463
Interoperability Issues for a Secure Mobile Agent Platform
15495414
A tool based methodology for development of automatically scalable and reusable parallel code
Program performance may be improved by efficiently programming some key sections of the software. We present a methodology for converting selected portions of source code into automatically scalable multithreaded routines, without forcing programmers to concentrate on parallel programming issues. These developed routines can be reused across various projects, operating systems and system architectures. To support this methodology two separate but tightly coupled tools have been developed -PARSA/sup (TM)/ software development environment (SDE) and the ThreadMan/sup (TM)/ thread manager. The SDE addresses programming issues by allowing a graphical object based approach to develop multithreaded routines that abstracts the users from parallel programming. ThreadMan manages the software developed using SDE. ThreadMan is a user-level thread manager that automatically spawns and schedules threads at runtime. Two examples have been developed using this methodology to demonstrate that there is virtually no degradation in performance when compared to sequential code, in a single processor system and scalability is achieved as the number of processors is increased.
38463254
Locating and Ranking XML Documents Based on Content and Structure Synopses
We present a new framework for indexing, locating and ranking XML documents based on content and structural synopses extracted from the documents. Instead of indexing each single element or term in a document, we extract a structural summary and a small number of data synopses from the document, which are indexed in an efficient way suitable for query evaluation. Our query language is XPath extended with full-text search. The result of query evaluation is a ranked list of document locations that best match the query. We propose a novel aggregated ranking scheme, which is integrated into the query evaluation to score the documents based on those data synopses. Our experimental evaluation shows that our indexing scheme outperforms the standard XML indexing scheme based on inverted lists and our ranking scheme is effective in terms of precision and recall.
13161865
On the Reliability and Additional Overhead of Reliable On-Demand Multicast Routing Protocol for Mobile Ad Hoc Networks
Multicasting is the transmission of datagrams to a group of hosts identified by a single destination address, providing simple and efficient communication for group-oriented applications. Many applications currently envisioned for mobile ad hoc networks require multicasting. Several multicasting protocols have been proposed for mobile ad hoc networks, one of the most popular being the On Demand Multicast Routing Protocol. This paper provides a review of ad hoc multicast routing protocols, focusing on MAODV, ODMRP and a variation of ODMRP called reliable-ODMRP. NS-2 simulations are used to compare the reliability and overhead of MAODV, ODMRP, and R-ODMRP.
40980541
Object-oriented programming (abstract): how to “scale up” CS 1
This past June, the National Science Foundation sponsored a workshop devoted to exploring the topic of how to integrate object-oriented programming g (OOP) concepts into the undergraduate curriculum Participants were chosen based, in pm on papers and lab materials that were submitted demonstrating practical experience with teaching 00P to undergraduates. One of the many surprises (to the conveners) to come out of the workshop was the large number of attendees who advocated teaching 00P (in a variety of languages) in the fiist programming course for majors (CS 1), and who had developed interesting approaches for doing so.
20665084
Parallel performance of two applications in the Boeing high performance computing benchmark suite
Abstract We describe our work to evaluate the performance of the parallel versions of two floating-point-intensive engineering applications from Boeing's high performance computing benchmark suite (BHPCBS) on emerging RISC parallel systems and PC clusters. The first application is a computational fluid dynamics (CFD) code, OVERFLOW, developed by NASA and used by Boeing for analysis and design of advanced aircraft. The second application is a prototype of a computational electromagnetics (CEM) code, developed by Boeing and used for radar cross-section studies. The distributed memory parallel versions of both applications use the message passing interface (MPI) standard for message passing. The goal of our work was to determine whether RISC parallel systems and PC clusters, which offer high performance at low cost, may be able to meet Boeing's computing requirements in the future. We describe the test environments for the studies, discuss parallelization issues and strategies and present performance data for the two applications.
62674005
Itinerant Agents for Mobile Computing
139273
Applications-driven parallel I/O
The authors investigate the needs of some massively parallel applications running on distributed-memory parallel computers at Argonne National Laboratory and identify some common parallel I/O operations. For these operations, routines were developed that hide the details of the actual implementation (such as the number of parallel disks) from the application, while providing good performance. An important feature is the ability for the application programmer to specify that a file be accessed either as a high-performance parallel file or as a conventional Unix file, simply by changing the value of a parameter on the file open call. These routines are examples of a parallel I/O abstraction that can enhance development, portability, and performance of I/O operations in applications. Some of the specific issues in their design and implementation in a distributed-memory toolset are discussed.
20578112
The art and science of computer graphics: a very depth-first approach to the non-majors course
This paper describes a course in computer graphics which is designed for students with little or no background in computer science. The course is centered around custom software which was designed with the pedagogical goals in mind. The goals of the course, the software, and some experiences at two institutions are discussed.