Leveraging the High Bandwidth of Last-Level Cache for HPC Seismic Imaging Applications

• DOI: 10.1145/3659914.3659936
• Publication Date: 2024-05-15T14:13:51Z
• Authors: Pavel Plotnitskii; Louis Beaurepaire; Long Qu; Kadir Akbudak; Hatem Ltaief; David Elliot Keyes
• Keywords: Memory bandwidth; Stencil; Memory footprint

We solve the 3D acoustic wave equation using finite-difference time-domain (FDTD) formulation in both first and second order. The FDTD approach is expressed as a stencil-based computational scheme with long-range discretization, i.e., 8th order space 2nd time, which routinely used oil gas industry environmental geophysics for high subsurface imaging fidelity purposes. Absorbing Boundary Conditions (ABCs) are employed to attenuate reflections from artificial boundaries. discretization engenders extensive data movement across memory subsystem may consequently impact kernel throughput due inherent memory-bound behavior of stencil operator, especially on systems facing starvation. first-order further exacerbates this phenomenon because it calculates pressure velocity fields, corresponds 1.6X footprint second-order formulation. To address bottleneck, we design, implement, deploy multicore wavefront diamond tiling temporal blocking (MWD-TB) boost performance seismic wavefield modeling by exploiting spatial reuse. MWD-TB leverages large capacity last-level cache (LLC) modern x86 extracts bandwidth underlying architecture. demonstrate numerical accuracy Salt3D model Society Exploration Geophysicists (SEG). Our implementations first- formulations achieve speedups up 3.5X 3X grid size AMD equipped LLC, respectively, compared traditional method alone.