Papers & Reports 2001

We consider the discontinuous Galerkin finite element discretization of first-order systems of conservation laws derivable as moments of kinetic Boltzmann equation. This includes well known conservation law systems such as the Euler equations of gas dynamics.
Energy Stable Flux Formulas for the Discontinuous Galerkin Discretization of First Order Nonlinear Conservation Laws, NAS Technical Report, NAS-01-001, February 2001.

We consider the differences between the available general purpose parameter study and job submission tools. These tools necessarily share many features, but frequently with differences in the way they are designed and implemented.
A Comparison of Parameter Study Creation and Job Submission Tools, NAS Technical Report, NAS-01-002, March 2001.

This report describes results of benchmark tests on the Origin 3000 system currently being installed at NAS. This machine will ultimately contain 1,024 R14K processors.
Comparison of Origin 2000 and Origin 3000 Using NAS Parallel Benchmarks, NAS Technical Report, NAS-01-003, May 2001.

This paper describes a new algorithm that improves the performance of application-controlled demand paging for the out-of-core visualization of data sets that are on either local disks or disks on remote servers.
Accelerating Demand Paging for Local and Remote Out-of-Core Visualization, NAS Technical Report, NAS-01-004, June 2001.

We present an extensible, object-oriented data model designed for field data entitled Field Model (FM). FM objects can represent a wide variety of fields, including fields of arbitrary dimension and node type.
Field Model: An Object-Oriented Data Model for Fields, NAS Technical Report, NAS-01-005, June 2001.

In this paper, we describe our software framework for control and observation of resources, services, and applications that supports such uses and we provide examples of how our framework can be used.
A Framework for Control and Observation in Distributed Environments, NAS Technical Report, NAS-01-006, June 2001.

This report describes results of benchmark tests on Steger, a 250 MHz Origin 2000 system with R10K processors, currently installed at the NASA Ames National Advanced Supercomputing (NAS) facility. For comparison purposes, the tests were also run on Lomax, a 400 MHz Origin 2000 with R12K processors.
Comparison of 250 MHz R10K Origin 2000 and 400 MHz Origin 2000 Using NAS Parallel Benchmarks, NAS Technical Report, NAS-01-007, July 2001.

CAPO (CAPTools-based Automatic Parallelizer using OpenMP) automates the insertion of compiler directives to facilitate parallel processing on shared memory parallel (SMP) machines. While CAPO is currently integrated seamlessly into CAPTools (developed at the University of Greenwich), CAPO is independently developed at NASA Ames Research Center as one of the components for the Legacy Code Modernization (LCM) project.
Code Parallelization with CAPO - A User Manual, NAS Technical Report, NAS-01-008, August 2001.

Though tools are available for creating and launching parameter studies in distributed environments, production-level users have shunned these tools for a variety of reasons. Ultimately, this is simply a result of the inability of these tools to provide anything more than a demonstration-level capability, rather than the flexibility and variety of industrial-strength capabilities that users actually require.
Production-Level Distributed Parametric Study Capabilities for the Grid, NAS Technical Report, NAS-01-009, October 2001.

Distributed computing systems have the potential to increase the usefulness of existing facilities for computation without adding anything physical, but that is realized only when necessary administrative features are in place. In a distributed environment, the best match is sought between a computing job to be run and a computer to run the job (global scheduling), which is a function that has not been required by conventional systems.
Pricing Computing Resources: Reading Between the Lines and Beyond, NAS Technical Report, NAS-01-010, November 2001.

In this paper we propose a master-slave architecture for multi-objective genetic algorithms on cycle scavengers. The architecture consists of slave computations running on computational nodes with relatively small populations, and a central master managing a large pareto front in a disc-based relational data base.
Towards 100,000 CPU Cycle-Scavenging by Genetic Algorithms, NAS Technical Report, NAS-01-011, September 2001.

We describe the design of a new method for the measurement of the performance of modern computer systems when solving scientific problems featuring irregular, dynamic memory accesses. The method involves the solution of a stylized heat transfer problem on an unstructured, adaptive grid.
Design of Unstructured Adaptive (UA) NAS Parallel Benchmark Featuring Irregular, Dynamic Memory Accesses, NAS Technical Report, NAS-01-012, December 2001.

A new approach to running complex, distributed MPI jobs using the MPICH-G2 library is described. This approach allows the user to switch between different versions of compilers, system libraries, MPI libraries, etc. via the "module" command. The key idea is a departure from the prescribed "(jobtype=mpi)" approach to running distributed MPI jobs
Using modules with MPICH-G2 (and "loose ends"), NAS Technical Report, NAS-01-013, July 2001.

We present new, efficient central schemes for multi-dimensional Hamilton-Jacobi equations. These non-oscillatory, non-staggered schemes are first- and second-order accurate and are designed to scale well with an increasing dimension.
Central Schemes for Multi-Dimensional Hamilton-JacobiEquations, NAS Technical Report, NAS-01-014, December 2001.