Re: [petsc-users] Best practices for solving Dense Linear systems

> On Aug 7, 2020, at 1:25 AM, Nidish wrote: > > Indeed - I was just using the default solver (GMRES with ILU). > > Using just standard LU (direct solve with "-pc_type lu -ksp_type preonly"), I > find elemental to be extremely slow even for a 1000x1000 matrix. > What about on one process?

Re: [petsc-users] Test convergence with non linear preconditioners

Great, that works. What would be the way to change the ilu level, I need to use ilu(1). I would assume that I can accomplish that by means of: -npc_fas_coarse_pc_type ilu -npc_fas_coarse_pc_ilu_levels 1 I noticed that the first line actually works, but I am not sure about the second one. Thanks,

Re: [petsc-users] Best practices for solving Dense Linear systems

On 8/7/20 8:52 AM, Barry Smith wrote: On Aug 7, 2020, at 1:25 AM, Nidish > wrote: Indeed - I was just using the default solver (GMRES with ILU). Using just standard LU (direct solve with "-pc_type lu -ksp_type preonly"), I find elemental to be extremely slow even for

Re: [petsc-users] Best practices for solving Dense Linear systems

> On Aug 7, 2020, at 12:26 PM, Nidish wrote: > > > > On 8/7/20 8:52 AM, Barry Smith wrote: >> >> >>> On Aug 7, 2020, at 1:25 AM, Nidish mailto:n...@rice.edu>> >>> wrote: >>> >>> Indeed - I was just using the default solver (GMRES with ILU). >>> >>> Using just standard LU (direct solve wi

Re: [petsc-users] Test convergence with non linear preconditioners

> On Aug 7, 2020, at 11:19 AM, Adolfo Rodriguez wrote: > > Great, that works. What would be the way to change the ilu level, I need to > use ilu(1). I would assume that I can accomplish that by means of: > > -npc_fas_coarse_pc_type ilu > -npc_fas_coarse_pc_ilu_levels 1 > > I noticed that t

Re: [petsc-users] Test convergence with non linear preconditioners

On Fri 7. Aug 2020 at 18:21, Adolfo Rodriguez wrote: > Great, that works. What would be the way to change the ilu level, I need > to use ilu(1). I > You want to use the option -xxx_pc_factor_levels 1 Where xxx is the appropriate FAS prefix level. See here https://www.mcs.anl.gov/petsc/petsc-