Evaluating cloud storage services for tightly-coupled applications

The emergence of Cloud computing has given rise to numerous attempts to study the portability of scientific applications to this new paradigm. Tightly-coupled applications are a common class of scientific HPC applications, which exhibit specific requirements previously addressed by supercomputers. A key challenge towards the adoption of the Cloud paradigm for such applications is data management. In this paper, we argue that Cloud storage services represent a suitable data storage and sharing option for Cloud applications. We evaluate a distributed storage plugin for Cumulus, an S3-compatible open-source Cloud service, and we conduct a series of experiments with an atmospheric modeling application running in a private Cloud deployed on the Grid'5000 testbed. Our results, obtained on up to 144 parallel processes, show that the application is able to scale with the size of the data and the number of processes, while storing 50 GB of output data on a Cloud storage service.