Global eScience using Computational Grids:
A Sabbatical Perspective
David Abramson
| Guard |
Nimrod
| Parametric computational experiments are becoming increasingly important in science and engineering as a means of exploring the behavior of complex systems. For example, an engineer may explore the behaviour of a wing by running a computational model of the airfoil multiple times while varying key parameters such as angle of attack, air speed, etc. The results of these multiple experiments yield a picture of how the wing behaves in different parts of parametric space. |  |
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Over the past several years, we have developed a specialized parametric modeling system called Nimrod. Nimrod uses a simple declarative parametric modeling language to express a parametric experiment and provides machinery that automates the task of formulating, running, monitoring, and collating the results from the multiple individual experiments. Equally important, Nimrod incorporates a distributed scheduling component that can manage the scheduling of individual experiments to idle computers in a local area network. Together, these features mean that even complex parametric experiments can be defined and run with little programmer effort. In many cases it is possible to establish a new experiment in minutes. Nimrod has been applied to a range of application areas, including Bioinformatics, Operations Research, Network Simulation, Electronic CAD, Ecological Modelling and Business Process Simulation |
| At the IEEE
Supercomputing (SC2003) in Phoenix, Arizona, together with colleagues
from the University of California,
San Diego (UCSD), colleagues in my research group and I performed
a large e-Science experiment using a computational Grid. We used
the Nimrod/G software to generate and distribute some 50,000 instances
of the GAMESS quantum chemistry package. The experiment ran
on up to 30 super-computers distributed over 10 countries. It spanned
test beds managed by the Pacific
Rim Applications and Grid Middleware Assembly (PRAGMA), The
Australian Grid Forum (AusGrid)
and the US-based TeraGrid . |
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The science behind this experiment concerned computing pseudo-potentials for organic functional groups, which play a key rôle in many chemical processes such as drug-receptor interactions. Generating more-accurate models of this interaction has enormous potential for the growing pharmaceutical products industry. In this demonstration we will show how Nimrod can be applied to problems in science and engineering. |