R-Adaptive Mesh Optimization to Enhance Finite Element Basis Compression

TL;DR

This paper introduces novel methods for reducing memory usage in finite element simulations by exploiting mesh redundancies through compression and adaptive optimization, enabling large-scale computations with limited memory.

Contribution

It presents two innovative techniques: dictionary-based data compression for mesh redundancy detection and r-adaptive mesh optimization to enhance such redundancies.

Findings

Memory reduction over 99% on large meshes

Effective detection and exploitation of mesh redundancies

Enhanced mesh structure improves compression efficiency

Abstract

Modern computing systems are capable of exascale calculations, which are revolutionizing the development and application of high-fidelity numerical models in computational science and engineering. While these systems continue to grow in processing power, the available system memory has not increased commensurately, and electrical power consumption continues to grow. A predominant approach to limit the memory usage in large-scale applications is to exploit the abundant processing power and continually recompute many low-level simulation quantities, rather than storing them. However, this approach can adversely impact the throughput of the simulation and diminish the benefits of modern computing architectures. We present two novel contributions to reduce the memory burden while maintaining performance in simulations based on finite element discretizations. The first contribution develops dictionary-based data compression schemes that detect and exploit the structure of the discretization, due to redundancies across the finite element mesh. These schemes are shown to reduce memory requirements by more than 99 percent on meshes with large numbers of nearly identical mesh cells. For applications where this structure does not exist, our second contribution leverages a recently developed augmented Lagrangian sequential quadratic programming algorithm to enable r-adaptive mesh optimization, with the goal of enhancing redundancies in the mesh. Numerical results demonstrate the effectiveness of the proposed methods to detect, exploit and enhance mesh structure on examples inspired by large-scale applications.