Domain Decomposition method on GPU cluster

Understand

Pallalel GPGPU computing for lattice QCD simulations has a bottleneck on the GPU to GPU data communication due to the lack of the direct data exchanging facility.

• In this work we investigate the performance of quark solver using the restricted additive Schwarz (RAS) preconditioner on a low cost GPU cluster.
• We expect that the RAS preconditioner with appropriate domaindecomposition and task distribution reduces the communication bottleneck.
• The GPU cluster we constructed is composed of four PC boxes, two GPU cards are attached to each box, and we have eight GPU cards in total.