[petsc-dev] [petsc-users] 2 levels of parallelism for ASM

[Barry Smith]

  Thomas,

     There is no way to have parallel subdomains in PETSc 3.1 for additive Schwarz but one of us has just added support in petsc-dev for exactly this approach. You can access petsc-dev via http://www.mcs.anl.gov/petsc/petsc-as/developers/index.html   Since this is a new not yet released feature please join the mailing list petsc-dev at mcs.anl.gov http://www.mcs.anl.gov/petsc/petsc-as/miscellaneous/mailing-lists.html and communicate issues regarding this top on that list.

   Barry



On Jan 24, 2011, at 8:09 AM, DUFAUD THOMAS wrote:

> Hi,
> I noticed that the local solution of an ASM preconditioner is performed on a single processor per domain, usually setting a KSP PREONLY to perform an ILU factorization.
> I would like to perform those local solution with a krylov method (GMRES) among a set of processors. 
> 
> Is it possible, for an ASM preconditioner, to set a subgroup of processors per domain and then define parallel sub-solver over a sub-communicator?
> 
> If it is the case how can I manage operation such as MatIncreaseOverlap?
> If it is not the case, does it exist a way to do that in PETSc?
> 
> Thanks, 
> 
> Thomas