> On 21 May 2025, at 10:41 AM, Edoardo Centofanti > <edoardo.centofant...@universitadipavia.it> wrote: > > > Dear all, > > I have some questions about the PCEXOTIC preconditioner: > > 1- While the type "wirebasket" seems clear to me, I do not understand what is > meant as "one dof per face" in the documentation referring to "face" type. Is > it intended as the interpolation on the centre of the face or some mean value? > > 2- Is it possible to change the overlap between the subdomains? > > 3- Are there any plans of extending the implementation to unstructured grids > (DMPlex-like)? The current one seems to rely heavily on DMDA > > 4- Running some preliminary tests on GPU with a code of mine that works on > CPU, I got the following error: > > ** On entry to cusparseSpMM_bufferSize(): dimension mismatch, matA.num_rows > (15405) != matC.num_rows (44955) with opA = CUSPARSE_OPERATION_NON_TRANSPOSE > > Is the preconditioner intended to run also on GPU or the error above comes > from the fact that this feature has yet to be tested/fully implemented? >
This preconditioner is very old and the code is barely maintained. There is a newer implementation of the GDSW preconditioner in PCMG, see https://urldefense.us/v3/__https://petsc.org/release/manualpages/PC/PCMGSetAdaptCoarseSpaceType/__;!!G_uCfscf7eWS!ZDnv3udGFNlZEC_MRfLAqwvcvCObnaAjMCeyaW__UaecBvN3MkXrzOPwJJUSHXo80-xOQdLNnSf_nLmUd7bZxg$ Thanks, Pierre > Thank you in advance, > Best, > Edoardo >
