petsc-3.6.2 2015-10-02
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Redistributes a matrix for load balancing, removing the rows that only have a diagonal entry and then applys a KSP to that new matrix Options for the redistribute preconditioners can be set with -redistribute_ksp_xxx <values> and -redistribute_pc_xxx <values>

Notes: Usually run this with -ksp_type preonly

If you have used MatZeroRows() to eliminate (for example, Dirichlet) boundary conditions for a symmetric problem then you can use, for example, -ksp_type preonly -pc_type redistribute -redistribute_ksp_type cg -redistribute_pc_type bjacobi -redistribute_sub_pc_type icc to take advantage of the symmetry.

This does NOT call a partitioner to reorder rows to lower communication; the ordering of the rows in the original matrix and redistributed matrix is the same.

Developer Notes: Should add an option to this preconditioner to use a partitioner to redistribute the rows to lower communication.

See Also

PCCreate(), PCSetType(), PCType (for list of available types), PCRedistributeGetKSP()

Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages