Clover Action for Blue Gene-Q and Iterative solvers for DWF

Abstract

In Lattice QCD, a major challenge in simulating physical quarks is the computational complexity of these simulations. In this proceeding, we describe the optimisation of Clover fermion action for Blue gene-Q architecture and how different iterative solvers behave for Domain Wall Fermion action. We find that the optimised Clover term achieved a maximum efficiency of 29.1% and 20.2% for single and double precision respectively for iterative Conjugate Gradient solver. For Domain Wall Fermion action (DWF) we found that Modified Conjugate Residual(MCR) as the most efficient solver compared to CG and GCR. We have developed a new multi-shift MCR algorithm that is 18.5% faster compared to multi-shift CG for the evaluation of rational functions in RHMC.