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Numerical weather prediction (NWP) experiments can be complex and time consuming; results depend on computational environments and numerous input parameters. Delays in learning and obtaining research results are inevitable. Students face disproportionate effort in the classroom or beginning graduate-level NWP research. Published NWP research is generally not reproducible, introducing uncertainty and slowing efforts that build on past results. This work exploits the rapid emergence of software container technology to produce a transformative research and education environment. The Weather Research and Forecasting (WRF) Model anchors a set of linked Linux-based containers, which include software to initialize and run the model, to analyze results, and to serve output to collaborators. The containers are demonstrated with a WRF simulation of Hurricane Sandy. The demonstration illustrates the following: 1) how the often-difficult exercise in compiling the WRF and its many dependencies is eliminated, 2) how sharing containers provides identical environments for conducting research, 3) that numerically reproducible results are easily obtainable, and 4) how uncertainty in the results can be isolated from uncertainty arising from computing system differences. Numerical experiments designed to simultaneously measure numerical reproducibility and sensitivity to compiler optimization provide guidance for interpreting NWP research. Reproducibility is independent from the operating system and hardware. Results here show numerically identical output on all computing platforms tested. Performance reproducibility is also demonstrated. The result is an infrastructure capable of accelerating classroom learning, graduate research, and collaborative science.

Evaluating experimental results in the field of computer systems is a challenging task, mainly due to the many changes in software and hardware that computational environments go through. In this position paper, we analyze salient features of container technology that, if leveraged correctly, can help reduce the complexity of reproducing experiments in systems research. We present a use case in the area of distributed storage systems to illustrate the extensions that we envision, mainly in terms of container management infrastructure. We also discuss the benefits and limitations of using containers as a way of reproducing research in other areas of experimental systems research.

Improving the performance and functionality of database system optimizers requires experimentation on real customer data. Often these data are of sensitive nature and the only way to keep them is by applying a non-reversible transformation to obfuscate them. However, in order that the database optimizer generates exactly the same query plans as for the sensitive data, the transformation has to preserve the order and some important properties of the data distribution. Unfortunately, existing data obfuscation techniques do not preserve all of these properties and therefore are not applicable in this context. In this paper we present a Desensitizer tool that we have developed for optimizer performance experiments of HP's Neoview high availability data warehousing product. The tool is based on novel numeric and string desensitization algorithms which are agnostic to the database system. We explain the core concepts behind the algorithms, how they preserve the required data properties and important implementation considerations that were made. We present the architecture of the Desensitizer tool and results of the extensive validation that we conducted.