Before spending time in an attempt to develop a parallel solution for a problem, determine whether or not the problem is one that can actually be parallelized.
Example of Parallelizable Problem:
Calculate the potential energy for each of several thousand independent conformations of a molecule. When done, find the minimum energy conformation.
This problem is able to be solved in parallel. Each of the molecular conformations is independently determinable. The calculation of the minimum energy conformation is also a parallelizable problem.the existing code also.