Performance optimized software strategies for unstructured-mesh applications in ocean modeling

海洋，大气和气候应用的精确模拟需要非常有效的数值方案和巨大的计算资源，在世界许多地方和许多活跃在这一领域的团体不容易获得。这种局限性也发挥了重要作用，因为结构化网格模型仍然是海洋科学领域共同体守则的支柱。在这个项目中，我们建议显着提高非结构化网格海洋应用程序的计算性能-专注于基于不连续Galerkin有限元法的求解器-并在同一时间，以减少实施新方法和应用程序的努力。第一个目标将通过利用一些旨在解决现有的性能瓶颈的技术来实现，这些技术包括区域分解和面向性能的自适应数值方案的新方法。第二个目标将通过诉诸现代软件设计策略来实现，包括代码生成和计算密集型内核的自动优化技术。这里提出的工作所带来的性能和代码设计的进步可以覆盖很多领域，使非结构化网格模型成为海洋科学的主流，特别是对HPC系统访问受限的用户可用。

Producing accurate simulations of ocean, atmosphere, and climate applications requires very efficient numerical schemes and huge computational resources not readily available in many parts of the world and to many groups active in this field. Such limitations also play a significant role in the fact that structured grid models still constitute the mainstay for community codes in the area of ocean science. In this project, we propose both to significantly improve the computational performance of unstructured grid ocean applications - focusing on a solver based on the discontinuous Galerkin finite element method - and, at the same time, to decrease the effort to implement new methods and applications. The first goal will be reached by utilizing a number of techniques aiming to address the existing performance bottlenecks; those include a new approach to domain decomposition and performance oriented adaptive numerical schemes. The second goal will be achieved by resorting to modern software design strategies, including code generation and automatic optimization techniques for the compute-intensive kernels. The performance and code design advances resulting from the work proposed here can cover a lot of ground towards making unstructured mesh models the mainstream of ocean science and, in particular, available to users with limited access to HPC systems.