>      Matt is right,
>
>      You should definitely try this before writing additional code. But you 
> need to put it in the code so it affects just this one scatter, not all the 
> scatters. So in the place where you create this "all to all" vector scatter 
> do the following.
>
>     PetscOptionsSetValue(NULL,"-vecscatter_alltoall","true");
>     VecScatterCreate...
>     PetscOptionsClearValue(NULL,"-vecscatter_alltoall")
>
>    You need to possibly change it slightly for different PETSc versions or 
> Fortran.
>
>     Please let us know how it goes,
>

Yes, thanks. I've told them to do this after Matt convinced me that
this is really that simple.  And this is a good suggestion on how to
target just one VecScatter. I was going to use a prefix, but this is
less error prone.

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