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Created by James Willenbring@jmwilleMaintainer

Teuchos::Time::wallTime() might not return a wall time but a CPU time

Created by: finkandreas

Teuchos:e:Time::wallTime() could not return actually a wall time, but the cpu time. Looking into the implementation, I've seen this piece of code:

#ifdef HAVE_MPI
        int mpiInitialized;
        MPI_Initialized(&mpiInitialized);
        if( mpiInitialized ) {
                return(MPI_Wtime());
        }
        else {
                clock_t start;
                start = clock();
                return( (double)( start ) / CLOCKS_PER_SEC );
        }

I realized it, when I did not initialize MPI, so I'll end up with the clock() call. On Linux the value returned is the CPU time, NOT a wallclock time, i.e. in an OpenMP programm this will give wrong results.