Hong, I also now just tested some previously PETSC_VERSION_LT(3,13,0) running code with C=A*B, Dense=Nest*Dense, all previously allocated prior to a call to MatMatMult and scall = MAT_REUSE_MATRIX. Sadly, it’s now broken. It is my fault for not having a test for this in https://gitlab.com/petsc/petsc/-/merge_requests/2069 <https://gitlab.com/petsc/petsc/-/merge_requests/2069>, sorry about that. [0]PETSC ERROR: Call MatProductSymbolic() first [0]PETSC ERROR: #1 MatProductNumeric() line 730 in /ccc/work/cont003/rndm/rndm/petsc/src/mat/interface/matproduct.c [0]PETSC ERROR: #2 MatMatMult() line 9335 in /ccc/work/cont003/rndm/rndm/petsc/src/mat/interface/matrix.c
Here is a reproducer (that will work OK with 3.12.4). diff --git a/src/mat/tests/ex195.c b/src/mat/tests/ex195.c index c72662bc3c..811de669c5 100644 --- a/src/mat/tests/ex195.c +++ b/src/mat/tests/ex195.c @@ -73,2 +73,3 @@ int main(int argc,char **args) ierr = MatMatMult(nest,B,MAT_REUSE_MATRIX,PETSC_DEFAULT,&C);CHKERRQ(ierr); + ierr = MatMatMult(nest,C,MAT_REUSE_MATRIX,PETSC_DEFAULT,&B);CHKERRQ(ierr); ierr = MatMatMultEqual(nest,B,C,10,&equal);CHKERRQ(ierr); $ make -f gmakefile test searchin=mat_tests-ex195 I believe this is very close to the topic at hand and issue #608, so maybe you could fix this as well in the same upcoming MR? Just let me know, I can have a crack it otherwise. Thanks, Pierre > On 22 Apr 2020, at 5:38 PM, Zhang, Hong <hzh...@mcs.anl.gov> wrote: > > Jose, Pierre and Stefano, > Now I understand the issue that Stefano raised. I plan to add > MatProductIsSupported(Wmat,&supported,&matproductsetfromoptions) > the flag 'supported' tells if the product is supported/implemented or not, > and the function pointer 'matproductsetfromoptions' gives the name of > MatProductSetFromOptions_xxx, (including basic implementation) or NULL. > > Let me know your suggestions. I'll list all of you as reviewer. > Hong > > From: Jose E. Roman <jro...@dsic.upv.es> > Sent: Wednesday, April 22, 2020 9:07 AM > To: Stefano Zampini <stefano.zamp...@gmail.com> > Cc: Zhang, Hong <hzh...@mcs.anl.gov>; Pierre Jolivet > <pierre.joli...@enseeiht.fr>; petsc-dev <petsc-dev@mcs.anl.gov> > Subject: Re: [petsc-dev] MATOP_MAT_MULT > > I agree with Pierre and Stefano. > Hong: your proposed solution would be fine, but MATOP_MATPRODUCT does not > exist yet, so I cannot try it. > I would like a solution along the lines of what Stefano suggests. It is not > too much trouble if it goes to master instead of maint. > > Thanks. > Jose > > > > El 22 abr 2020, a las 15:26, Stefano Zampini <stefano.zamp...@gmail.com> > > escribió: > > > > > >> > >> MatProductCreateWithMat(A,Vmat,NULL,Wmat); > >> MatProductSetType(Wmat,MATPRODUCT_AB); > >> MatHasOperation(Wmat,MATOP_MATPRODUCT,&flg); //new support, it calls > >> MatProductSetFromOptions(Wmat) > > > > Hong, this would go in the direction I was outlining here > > https://gitlab.com/petsc/petsc/-/issues/608 > > <https://gitlab.com/petsc/petsc/-/issues/608> > > How about also adding something like > > > > MatProductIsImplemented(Wmat,&flg) > > > > That returns true if a specific implementation is available? This way > > > > This way, if we use both queries, we can assess the presence of the basic > > fallbacks too, i.e. > > > > MatHasOperation(Wmat,MATOP_MATPRODUCT,&flg1) > > MatProductIsImplemented(Wmat,&flg2) > > > > If flg1 is false, no support at all > > If flg1 is true and flg2 is false -> Basic implementation (i.e, MatShell > > with products inside) > > If flg1 and flg2 are both true -> Specific implementation available. > > > >> if (V->vmm && flg) { > >> MatProductSymbolic(Wmat); > >> MatProductNumeric(Wmat); > >> } else { > >> MatDestroy(Wmat); > >> ... > >> } > >> Hong > >> > >> > >> From: Jose E. Roman <jro...@dsic.upv.es> > >> Sent: Tuesday, April 21, 2020 11:21 AM > >> To: Pierre Jolivet <pierre.joli...@enseeiht.fr> > >> Cc: Zhang, Hong <hzh...@mcs.anl.gov>; petsc-dev <petsc-dev@mcs.anl.gov> > >> Subject: Re: [petsc-dev] MATOP_MAT_MULT > >> > >> > >> > >> > El 21 abr 2020, a las 17:53, Pierre Jolivet <pierre.joli...@enseeiht.fr> > >> > escribió: > >> > > >> > > >> > > >> >> On 21 Apr 2020, at 5:22 PM, Zhang, Hong <hzh...@mcs.anl.gov> wrote: > >> >> > >> >> Pierre, > >> >> MatMatMult_xxx() is removed from MatOps table. > >> > > >> > Shouldn’t there be a deprecation notice somewhere? > >> > There is nothing about MATOP_MAT_MULT in the 3.13 changelog > >> > https://www.mcs.anl.gov/petsc/documentation/changes/313.html > >> > <https://www.mcs.anl.gov/petsc/documentation/changes/313.html> > >> > For example, I see that in SLEPc, José is currently making these checks, > >> > which are in practice useless as they always return > >> > PETSC_FALSE?https://gitlab.com/slepc/slepc/-/blob/master/src/sys/classes/bv/impls/contiguous/contig.c#L191 > >> > (Maybe José is aware of this and this is just for testing) > >> > >> No, I was not aware of this. Thanks for bringing this up. Now in 3.13 we > >> are always doing the slow version (column by column), so yes I am > >> interested in a solution for this. > >> > >> > > >> >> MatMatMult() is replaced by > >> >> MatProductCreate() > >> >> MatProductSetType(,MATPRODUCT_AB) > >> >> MatProductSetFromOptions() > >> >> MatProductSymbolic() > >> >> MatProductNumeric() > >> >> > >> >> Where/when do you need query a single matrix for its product operation? > >> > > >> > I didn’t want to bother at first with the new API, because I’m only > >> > interested in C = A*B with C and B being dense. > >> > Of course, I can update my code, but if I understand Stefano’s issue > >> > correctly, and let’s say my A is of type SBAIJ, for which there is no > >> > MatMatMult, the code will now error out in the MatProduct? > >> > There is no fallback mechanism? Meaning I could in fact _not_ use the > >> > new API and will just have to loop on all columns of B, even for AIJ > >> > matrices. > >> > > >> > Thanks, > >> > Pierre > >> > > >> >> Hong > >> >> > >> >> From: petsc-dev <petsc-dev-boun...@mcs.anl.gov> on behalf of Pierre > >> >> Jolivet <pierre.joli...@enseeiht.fr> > >> >> Sent: Tuesday, April 21, 2020 7:50 AM > >> >> To: petsc-dev <petsc-dev@mcs.anl.gov> > >> >> Subject: [petsc-dev] MATOP_MAT_MULT > >> >> > >> >> Hello, > >> >> Am I seeing this correctly? > >> >> #include <petsc.h> > >> >> > >> >> int main(int argc,char **args) > >> >> { > >> >> Mat A; > >> >> PetscBool hasMatMult; > >> >> PetscErrorCode ierr; > >> >> > >> >> ierr = PetscInitialize(&argc,&args,NULL,NULL);if (ierr) return ierr; > >> >> ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr); > >> >> ierr = MatSetType(A,MATMPIAIJ);CHKERRQ(ierr); > >> >> ierr = MatHasOperation(A,MATOP_MAT_MULT,&hasMatMult);CHKERRQ(ierr); > >> >> printf("%s\n", PetscBools[hasMatMult]); > >> >> ierr = PetscFinalize(); > >> >> return ierr; > >> >> } > >> >> > >> >> => FALSE > >> >> > >> >> I believe this is a regression (or at least an undocumented change) > >> >> introduced here:https://gitlab.com/petsc/petsc/-/merge_requests/2524/ > >> >> <https://gitlab.com/petsc/petsc/-/merge_requests/2524/> > >> >> I also believe Stefano raised a similar point there: > >> >> https://gitlab.com/petsc/petsc/-/issues/608 > >> >> <https://gitlab.com/petsc/petsc/-/issues/608> > >> >> This is a performance killer in my case because I was previously using > >> >> this check to know whether I could use MatMatMult or had to loop on all > >> >> columns and call MatMult on all of them. > >> >> There is also a bunch of (previously functioning but now) broken code, > >> >> e.g.,https://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/transpose/transm.c.html#line105 > >> >> > >> >> <https://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/transpose/transm.c.html#line105>or > >> >> > >> >> https://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/nest/matnest.c.html#line2105 > >> >> > >> >> <https://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/nest/matnest.c.html#line2105> > >> >> Is this being addressed/documented? > >> >> > >> >> Thanks, > >> >> Pierre > >> > > >