HR: 0800h
AN: IN11B-0463 [Abstracts]
TI: Pegasus: Providing Computation Management for Earth Science Applications
AU: Deelman, E
EM: deelman@isi.edu
AF: USC Information Sciences Institute, 4676 Admiralty Way, Marina del Rey, CA 90292, United
States
AU: Callaghan, S
EM: scottcal@usc.edu
AF: Southern California Earthquake Center, 3651 Trousdale Parkway, Los Angeles, CA 90089,
United States
AU: Graves, R
EM: robert.graves@urscorp.com
AF: Southern California Earthquake Center, 3651 Trousdale Parkway, Los Angeles, CA 90089,
United States
AU: Jordan, T H
EM: tjordan@usc.edu
AF: Southern California Earthquake Center, 3651 Trousdale Parkway, Los Angeles, CA 90089,
United States
AU: Juve, G
EM: juve@usc.edu
AF: Southern California Earthquake Center, 3651 Trousdale Parkway, Los Angeles, CA 90089,
United States
AU: Kesselman, C
EM: carl@isi.edu
AF: USC Information Sciences Institute, 4676 Admiralty Way, Marina del Rey, CA 90292, United
States
AU: * Maechling, P
EM: maechlin@usc.edu
AF: Southern California Earthquake Center, 3651 Trousdale Parkway, Los Angeles, CA 90089,
United States
AU: Mehta, G
EM: gmehta@isi.edu
AF: USC Information Sciences Institute, 4676 Admiralty Way, Marina del Rey, CA 90292, United
States
AU: Meyers, D
EM: dpmeyers@usc.edu
AF: Southern California Earthquake Center, 3651 Trousdale Parkway, Los Angeles, CA 90089,
United States
AU: Okaya, D
EM: okaya@usc.edu
AF: Southern California Earthquake Center, 3651 Trousdale Parkway, Los Angeles, CA 90089,
United States
AU: Su, M
EM: meisu@isi.edu
AF: USC Information Sciences Institute, 4676 Admiralty Way, Marina del Rey, CA 90292, United
States
AU: Vahi, K
EM: vahi@isi.edu
AF: USC Information Sciences Institute, 4676 Admiralty Way, Marina del Rey, CA 90292, United
States
AU: Wong-Barnum, M
EM: mona@sdsc.edu
AF: San Diego Supercomputer Center, 9500 Gilman Drive, La Jolla, CA 92093, United States
AB:
Earth science applications such as those being developed within the Southern California Earthquake Center
(SCEC) require the coordination of hundreds of thousands of computation and data management tasks running
on the national cyberinfrastructure resources such as the TeraGrid. Such coordination cannot be done by a single
person; rather, automated techniques such as those provided by the Pegasus workflow management system
need to be put in place. In this talk we will describe the Pegasus software from the point of view of an application
and show examples of use of Pegasus in SCEC applications such as CyberShake and Earthworks.
The SCEC CyberShake Project uses physics-based models of earthquake processes and integrates these
models into a scientific framework for seismic hazard analysis and risk management. As a result CyberShake
aims to produce more accurate hazard curves for the Southern California area. These hazard curves can then be
interpolated to produce a Probabilistic Seismic Hazard Analysis (PSHA) map for a given area. Probabilistic
seismic hazard maps indicate the likelihood of seeing a specific amount of surface motion within a specified
period of time. PSHA is used (among other things) to determine the placement and design of buildings and other
structures.
The SCEC Earthworks Science Gateway is designed to compute and distribute ground-motion simulations for
use in risk assessment and earthquake-engineering analysis. Earthworks uses high-performance simulation
software called Anelastic Wave Propagation (AWP) models. AWP's compute the
propagation, interference, and attenuation of seismic waves as they travel from a fault rupture to a target site. The
results are typically vector-valued ground velocity values as a function of time, from which essentially any intensity
measure can be computed.
Both CyberShake and Earthworks require high-performance, multi-processor resources such as those provided
by the NSF-funded TeraGrid to perform the computations in a reasonable amount of time, such as in hours
instead of weeks. However, in order to use these resources easily and efficiently, tools such as Pegasus, Condor
DAGMan, and grid-based services such as GridFTP need to be used. Pegasus is designed to help scientists
describe a series of scientific computations (a workflow) in abstract terms without worrying about the details of
the underlying infrastructure. These initial workflow descriptions are abstract, by which we mean that the
workflows do not identify the particular resources needed for execution. The selection of specific resources to use
is automatically performed by Pegasus which selects which resources to use, makes sure that the data is
delivered to the computations, and delivers the results to the scientist. As a result Pegasus generates a concrete
workflow, that is, an executable workflow which is executed reliably on the TeraGrid resources.
Pegasus and DAGMan are not application or execution environment-specific. They have been applied in a variety
of application from astronomy, gravitational-wave physics, neuroscience, and others running on national
cyberinfrastructure as well as campus clusters, Condor pools, and desktops.
UR: http://pegasus.isi.edu/
DE: 0520 Data analysis: algorithms and implementation
DE: 0525 Data management
DE: 0530 Data presentation and visualization
DE: 0545 Modeling (4255)
DE: 0594 Instruments and techniques
SC: Earth and Space Science Informatics [IN]
MN: 2007 Fall Meeting