Carrying out science at extreme scale is the next generational challenge facing the broad field of scientific research. Cloud computing offers to potential for an increasing number of researchers to have ready access to the large scale compute resources required to tackle new challenges in their field. Unfortunately barriers of complexity remain for researchers untrained in cloud programming. In this paper we examine how cloud based architectures can be used to solve large scale research experiments in a manner that is easily accessible for researchers with limited programming experience, using their existing computational tools. We examine the top challenges identified in our own large-scale science experiments running on the Windows Azure platform and then describe a Cloud-based parameter sweep prototype (dubbed Cirrus) which provides a framework of solutions for each challenge.

Scientists working in eScience environments often use workflows to carry out their computations. Since the workflows evolve as the research itself evolves, these workflows can be a tool for tracking the evolution of the research. Scientists can trace their research and associated results through time or even go back in time to a previous stage and fork to a new branch of research. In this paper we introduce the workflow evolution framework (EVF), which is demonstrated through implementation in the Trident workflow workbench. The primary contribution of the EVF is efficient management of knowledge associated with workflow evolution. Since we believe evolution can be used for workflow attribution, our framework will motivate researchers to share their workflows and get the credit for their contributions.

Applying high level parallel runtimes to data/compute intensive applications is becoming increasingly common. The simplicity of the MapReduce programming model and the availability of open source MapReduce runtimes such as Hadoop, are attracting more users to the MapReduce programming model. Microsoft has released DryadLINQ for academic use, allowing users to experience a new programming model and a runtime that is capable of performing large scale data/compute intensive analyses. In this paper, we present our experience in applying DryadLINQ for a series of scientific data analysis applications, identify their mapping to the DryadLINQ programming model, and compare their performances with Hadoop implementations of the same applications.

In our demonstration we present Trident, a scientific workflow workbench built on top of a commercial workflow system to leverage existing functionality to the extent possible. Trident is being developed in collaboration with the scientific computing community for use in a number of ongoing eScience projects that make use of scientific workflows, in particular the Pan-STARRS sky survey project and the Ocean Observatory Initiative. In our demonstration of Trident we will illustrate the ability to utilize both local and cloud resources for storage and execution, as well as services such as provenance, monitoring, logging and scheduling workflows over clusters. Our goal is to release Trident in early 2009 as an open source accelerator for others to use for eScience projects and to continue extending with support for new workflow features and services.