We don't have a "true" parallel SOR or GS that uses coloring. We only support a domain decomposition type SOR/GS where each process updates its local values, then they exchange ghost points and repeat.
You can us -ksp_type richardson -pc_type sor for this. http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/PC/PCSOR.html lists all the options. > On Mar 12, 2017, at 1:31 PM, 丁老师 <[email protected]> wrote: > > How to solve the Ax=b with parallel SOR or parallel GS only. > > >
