[petsc-dev] [petsc-maint #49008] Problems with VecDotNorm2

[Satish Balay]

Ah - I see you wanted me to use 1-patch-vecdotnorm2-table.diff - but I
used 2-patch-vecdotnorm2-query.diff.

I can do as Jose suggested: 2-patch-vecdotnorm2-query.diff to
petsc-3.1 and pull/merge/change petsc-dev to
2-patch-vecdotnorm2-query.diff

Satish

On Thu, 8 Jul 2010, Barry Smith wrote:

> 
>   Ok, let's go with it then.
> 
>    Thanks
> 
>   Barry
> 
> On Jul 8, 2010, at 6:59 PM, Satish Balay wrote:
> 
> > Barry,
> > 
> > I've added patch-vecdotnorm2-query.diff to petsc-31 and ran a couple
> > of builds with tests - and they ran fine.
> > 
> > Satish
> > 
> > On Thu, 8 Jul 2010, Barry Smith wrote:
> > 
> >> 
> >>   Satish,
> >> 
> >>    Can you try to apply solution 1 to 3.1 and see if the tests are ok?
> >> 
> >>   Barry
> >> 
> >> On Jul 8, 2010, at 9:56 AM, Jose E. Roman wrote:
> >> 
> >>> 
> >>> On 07/07/2010, Barry Smith wrote:
> >>> 
> >>>> 
> >>>> On Jul 6, 2010, at 9:49 AM, Jose E. Roman wrote:
> >>>> 
> >>>>> Dear all,
> >>>>> 
> >>>>> We at SLEPc have included a custom implementation of vectors that emulates block vectors in the spirit of PetscExt: v=[v1' v2']' where v1 and v2 are PETSc vectors. This is required for some new SLEPc solvers. With this new type of vectors, we avoid the VecGetArray/VecRestoreArray operations, which would imply array copies, and overload any other required operation. The only place outside SLEPc where these vectors are used is as arguments to KSPSolve.
> >>>>> 
> >>>>> The problem is VecDotNorm2, which is used in KSPSolve_BCGS and KSPSolve_GCR_cycle and invokes VecGetArray. VecDotNorm2 cannot be overloaded as the other functions, since it is not included in the _VecOps table. Therefore we cannot use KSP=bcgsl with our new solvers. A fix for us would be to promote VecDotNorm2 to be a true Vec operation
> >>>> 
> >>>> 
> >>>> I have no objection to upgrading VecDotNorm2() to be a virtual function. 
> >>>> 
> >>>> 
> >>>>> . If possible, it would be nice that the fix would be included in petsc-3.1.
> >>>> 
> >>>> We really don't like to make such a big change in a patch but if you make the change the change to 3.1 and test it then I have no objection.
> >>>> 
> >>>> Barry
> >>>> 
> >>>>> 
> >>>>> Thanks,
> >>>>> Jose
> >>>>> 
> >>>>> PS. We plan to release slepc-3.1 in a few weeks.
> >>>>> 
> >>>>> 
> >>>> 
> >>> 
> >>> I am attaching two possible solutions to our problem.
> >>> 
> >>> 1) patch-vecdotnorm2-table.diff --> this is the solution suggested initially. The problem is that if it is included in petsc-3.1 then the ABI will be incompatible with previous patches.
> >>> 
> >>> 2) patch-vecdotnorm2-query.diff --> this uses PetscObjectQueryFunction so that the functionality can be replaced from outside. You may not like this hack but it maintains ABI compatibility.
> >>> 
> >>> You may decide to put 2) into petsc-release-3.1 and 1) into petsc-dev.
> >>> 
> >>> Note that both patchfiles are with respect to petsc-release-3.1.
> >>> 
> >>> Cheers,
> >>> Jose
> >>> 
> >>> 
> >>> <patch-vecdotnorm2-query.diff><patch-vecdotnorm2-table.diff>
> >> 
> >> 
> >> 
> > 
> > 
> 
> 
>