This paper describes the Pegasus framework that can be used to map complex scientific workflows onto distributed resources. Pegasus enables users to represent the workflows at an abstract level without needing to worry about the particulars of the target execution systems. The paper describes general issues in mapping applications and the functionality of Pegasus. We present the results of improving application performance through workflow restructuring.

Abstract: In grid workflow systems, to verify fixed-time constraints efficiently at the run-time execution stage, some checkpoints are often selected so that we only need to conduct the fixed-time constraint verification at such checkpoints rather than at all activity points. However, the existing typical checkpoint selection strategies are inefficient and/or ineffective because they may incur some unnecessary verification by selecting some unnecessary checkpoints or omit some necessary verification by omitting some necessary checkpoints. Therefore, in this paper, based on the run-time activity completion duration, we develop a new checkpoint selection strategy that is more efficient and effective than the existing typical checkpoint selection strategies. The final comparison and quantitative evaluation further demonstrate this point. 1

© 2008 Boyle et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License