[Dune] Performace of ISTL

[Patrick Leidenberger]

Hi Markus

>> That's right, I am sorry. I make a better comparison with the same mesh 
>> like yesterday:
>> Trilinos with Jacobi and CG:  2 sec, 40 iteratrions residual: 1.05e-8
>> Dune     with Jacobi and CG: 30 sec, 40 iteratrions residual: 1.05e-8
>> And I don't forget a '0' for trilinos!
>>
> 
> Did you compile Dune with optimization CXXFLAGS="-O3 -DNDEBUG" and
> without setting DUNE_ISTL_WITH_CHECKING?

The test above was done with -O2 and without setting 
DUNE_ISTL_WITH_CHECKING.

Now I recompile exactly like you want to have it, but the performance is 
exactly the same! No speedup.

Patrick