Matrix free preconditioning

[Tim Kroeger]

Dear PETSc developers,

Can you give me some advice on possible/recommended choices of 
preconditioners in the case of matrix free ksp?  I create my matrix 
using MatCreateShell().  The matrix is not symmetric.  I understand 
that the typical preconditioners like ILU or JACOBI will not work 
since they require access to the matrix entries.  Is there any good 
precoditioner that will work?

Best Regards,

Tim

-- 
Dr. Tim Kroeger                                        Phone +49-421-218-7710
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