[petsc-users] MatSetValues with openMP and no data races

[Lawrence Mitchell]

On 12/10/17 14:40, Guillaume Emond wrote:
> Goodmorning,
> 
> I would like to clarify a point about the insertion of values with  
> MatSetValues in a openMP loop. I know these routines are not thread  
> safe. But, in our situation, we used a graph coloring algorithm on our  
> mesh to make sure no adjacent element is inserted at the same time so  
> no data races occurs when inserting values. Could these routines be  
> used with openmp then or is there some internal variables that would  
> not be thread safe?

The MatStash used for saving and then later communicating off process
entries during AssemblyEnd is, I believe, not thread safe.

Cheers,

Lawrence