[Omp] OpenMP and Intel compiler

[Laksono Adhianto]

Hi

I use Intel compiler v7.1 to compile a hybrid MPI/OpenMP and a pure MPI program
on Linux Intel Itanium2 clusters.

I found out that if the program is compiled in debugging mode (with -g option),
then the hybrid MPI/OpenMP is twice faster than pure MPI.
However, if compiled without debugging mode, then pure MPI is three times faster
then hybrid MPI/OpenMP.

I also tried with SWEEP3D benchmark, and the result is approximately the same
(i.e. with debugging mode hybrid MPI/OpenMP is much faster than pure MPI).

Is this normal or it's just my 'luck' ?
Well, "intuitively" either with or without debugging mode, the result should be
the same ?

Regards,

------
Laksono Adhianto