[petsc-users] Best practices for solving Dense Linear systems

[Nidish]

I'm relatively new to PETSc, and my applications involve (for the most 
part) dense matrix solves.

I read in the documentation that this is an area PETSc does not 
specialize in but instead recommends external libraries such as 
Elemental. I'm wondering if there are any "best" practices in this 
regard. Some questions I'd like answered are:

1. Can I just declare my dense matrix as a sparse one and fill the whole 
matrix up? Do any of the others go this route? What're possible 
pitfalls/unfavorable outcomes for this? I understand the memory overhead 
probably shoots up.
2. Are there any specific guidelines on when I can expect elemental to 
perform better in parallel than in serial?

Of course, I'm interesting in any other details that may be important in 
this regard.

Thank you,
Nidish