On Tue, Feb 7, 2017 at 7:53 AM, Michel Kern <michel.k...@inria.fr> wrote:
> Thanks Mat, > > according tot he hypre documentation, pilut is "no longer supported by the > hypre team", as less efficient than Euclid, so I wouldn't consider an > option. I wsa looking for a "natural" upgrade path. > I don't know of another ILU. I have never understood the use of ILU. It is a fragile, not very scalable algorithm which is soundly beaten in every arena where we understand the problem. I also do not understand why it is used as part of CPR. I can't believe that is the best way to solve the problem. But maybe I do not understand. Thanks, Matt > The problems we've looked at for the moment can be up to a few millions > cells (that's the size of the pressure block, the saturation block is > larger, but should be easier to solve). We're aiming for 10^6 cells, and > 10^3 cores. > Yes, direct methods deserve a second look ! > > Michel > > ------------------------------ > > On Tue, Feb 7, 2017 at 2:49 AM, Michel Kern <michel.k...@inria.fr> wrote: > >> I have a code that uses euclid for ILU preconditioning (as part of a >> CPR-AMG preconditioner for a mulitphase flow solver). As noted in the >> release notes, euclid is no longer supported starting from 3.6. What is the >> recommended replacement ? Is block Jacobi plus a local solver an >> alternative ? >> > > There is pilut from Hypre. > > How big is the problem? Did you try sparse direct on it (SuperLU, MUMPS)? > > Thanks, > > Matt > > >> Thanks >> Michel >> >> -- >> Michel Kern >> Centre de Recherche Inria de Paris, Maison de la Simulation >> 2 rue Simone Iff, bureau A413, Digiteo Labs, bât 565, CEA >> Saclay >> 75012 Paris 91191 Gif-sur-Yvette >> cedex >> tel. : +33 (0)1 80 49 42 36 <+33%201%2080%2049%2042%2036>, >> tel. : +33 (0)1 69 08 58 32 <+33%201%2069%2008%2058%2032> >> >> >> > > > -- > What most experimenters take for granted before they begin their > experiments is infinitely more interesting than any results to which their > experiments lead. > -- Norbert Wiener > > > > > -- > Michel Kern > Centre de recherche Inria de Paris, Maison de la Simulation, > 2 rue Simone Iff, bureau A413, Digiteo Labs, bât. 565, CEA Saclay > 75012 Paris 91191 Gif-sur-Yvette Cedex > tel. : +33 (0)1 80 49 42 36 <+33%201%2080%2049%2042%2036>, tel. : +33 > (0)1 69 08 58 32 <+33%201%2069%2008%2058%2032> > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener